Merge pull request #3852 from minrk/isort

Use isort for import formatting

.pre-commit-config.yaml

@@ -18,10 +18,10 @@ repos:
           - --py36-plus
 
   # Autoformat: Python code
-  - repo: https://github.com/asottile/reorder_python_imports
+  - repo: https://github.com/pycqa/isort
-    rev: v3.0.1
+    rev: 5.10.1
     hooks:
-      - id: reorder-python-imports
+      - id: isort
 
   # Autoformat: Python code
   - repo: https://github.com/psf/black

docs/source/conf.py

@@ -56,13 +56,15 @@ todo_include_todos = False
 # Set the default role so we can use `foo` instead of ``foo``
 default_role = 'literal'
 
-# -- Config -------------------------------------------------------------
-from jupyterhub.app import JupyterHub
-from docutils import nodes
-from sphinx.directives.other import SphinxDirective
 from contextlib import redirect_stdout
 from io import StringIO
 
+from docutils import nodes
+from sphinx.directives.other import SphinxDirective
+
+# -- Config -------------------------------------------------------------
+from jupyterhub.app import JupyterHub
+
 # create a temp instance of JupyterHub just to get the output of the generate-config
 # and help --all commands.
 jupyterhub_app = JupyterHub()

examples/azuread-with-group-management/jupyterhub_config.py

@@ -7,9 +7,10 @@ to enable testing without administrative privileges.
 c = get_config()  # noqa
 c.Application.log_level = 'DEBUG'
 
-from oauthenticator.azuread import AzureAdOAuthenticator
 import os
 
+from oauthenticator.azuread import AzureAdOAuthenticator
+
 c.JupyterHub.authenticator_class = AzureAdOAuthenticator
 
 c.AzureAdOAuthenticator.client_id = os.getenv("AAD_CLIENT_ID")

examples/custom-scopes/grades.py

@@ -5,12 +5,9 @@ from urllib.parse import urlparse
 
 from tornado.httpserver import HTTPServer
 from tornado.ioloop import IOLoop
-from tornado.web import Application
+from tornado.web import Application, RequestHandler, authenticated
-from tornado.web import authenticated
-from tornado.web import RequestHandler
 
-from jupyterhub.services.auth import HubOAuthCallbackHandler
+from jupyterhub.services.auth import HubOAuthCallbackHandler, HubOAuthenticated
-from jupyterhub.services.auth import HubOAuthenticated
 from jupyterhub.utils import url_path_join
 
 SCOPE_PREFIX = "custom:grades"

examples/external-oauth/whoami-oauth-basic.py

@@ -5,13 +5,10 @@ so all URLs and requests necessary for OAuth with JupyterHub should be in one pl
 """
 import json
 import os
-from urllib.parse import urlencode
+from urllib.parse import urlencode, urlparse
-from urllib.parse import urlparse
 
-from tornado import log
+from tornado import log, web
-from tornado import web
+from tornado.httpclient import AsyncHTTPClient, HTTPRequest
-from tornado.httpclient import AsyncHTTPClient
-from tornado.httpclient import HTTPRequest
 from tornado.httputil import url_concat
 from tornado.ioloop import IOLoop
 

examples/server-api/start-stop-server.py

@@ -16,7 +16,6 @@ import time
 
 import requests
 
-
 log = logging.getLogger(__name__)
 
 

examples/service-announcement/announcement.py

@@ -3,9 +3,7 @@ import datetime
 import json
 import os
 
-from tornado import escape
+from tornado import escape, ioloop, web
-from tornado import ioloop
-from tornado import web
 
 from jupyterhub.services.auth import HubAuthenticated
 

examples/service-fastapi/app/models.py

@@ -1,8 +1,5 @@
 from datetime import datetime
-from typing import Any
+from typing import Any, Dict, List, Optional
-from typing import Dict
-from typing import List
-from typing import Optional
 
 from pydantic import BaseModel
 

examples/service-fastapi/app/security.py

@@ -1,9 +1,7 @@
 import json
 import os
 
-from fastapi import HTTPException
+from fastapi import HTTPException, Security, status
-from fastapi import Security
-from fastapi import status
 from fastapi.security import OAuth2AuthorizationCodeBearer
 from fastapi.security.api_key import APIKeyQuery
 

examples/service-fastapi/app/service.py

@@ -1,14 +1,9 @@
 import os
 
-from fastapi import APIRouter
+from fastapi import APIRouter, Depends, Form, Request
-from fastapi import Depends
-from fastapi import Form
-from fastapi import Request
 
 from .client import get_client
-from .models import AuthorizationError
+from .models import AuthorizationError, HubApiError, User
-from .models import HubApiError
-from .models import User
 from .security import get_current_user
 
 # APIRouter prefix cannot end in /

examples/service-whoami-flask/whoami-flask.py

@@ -7,16 +7,10 @@ import os
 import secrets
 from functools import wraps
 
-from flask import Flask
+from flask import Flask, Response, make_response, redirect, request, session
-from flask import make_response
-from flask import redirect
-from flask import request
-from flask import Response
-from flask import session
 
 from jupyterhub.services.auth import HubOAuth
 
-
 prefix = os.environ.get('JUPYTERHUB_SERVICE_PREFIX', '/')
 
 auth = HubOAuth(api_token=os.environ['JUPYTERHUB_API_TOKEN'], cache_max_age=60)

examples/service-whoami/whoami-oauth.py

@@ -10,12 +10,9 @@ from urllib.parse import urlparse
 
 from tornado.httpserver import HTTPServer
 from tornado.ioloop import IOLoop
-from tornado.web import Application
+from tornado.web import Application, RequestHandler, authenticated
-from tornado.web import authenticated
-from tornado.web import RequestHandler
 
-from jupyterhub.services.auth import HubOAuthCallbackHandler
+from jupyterhub.services.auth import HubOAuthCallbackHandler, HubOAuthenticated
-from jupyterhub.services.auth import HubOAuthenticated
 from jupyterhub.utils import url_path_join
 
 

examples/service-whoami/whoami.py

@@ -10,9 +10,7 @@ from urllib.parse import urlparse
 
 from tornado.httpserver import HTTPServer
 from tornado.ioloop import IOLoop
-from tornado.web import Application
+from tornado.web import Application, RequestHandler, authenticated
-from tornado.web import authenticated
-from tornado.web import RequestHandler
 
 from jupyterhub.services.auth import HubAuthenticated
 

jupyterhub/__init__.py

@@ -1,2 +1 @@
-from ._version import __version__
+from ._version import __version__, version_info
-from ._version import version_info

jupyterhub/_data.py

@@ -4,7 +4,7 @@
 def get_data_files():
     """Walk up until we find share/jupyterhub"""
     import sys
-    from os.path import join, abspath, dirname, exists, split
+    from os.path import abspath, dirname, exists, join, split
 
     path = abspath(dirname(__file__))
     starting_points = [path]

jupyterhub/alembic/env.py

@@ -3,8 +3,7 @@ import sys
 from logging.config import fileConfig
 
 from alembic import context
-from sqlalchemy import engine_from_config
+from sqlalchemy import engine_from_config, pool
-from sqlalchemy import pool
 
 # this is the Alembic Config object, which provides
 # access to the values within the .ini file in use.
@@ -13,6 +12,7 @@ config = context.config
 # This line sets up loggers basically.
 if 'jupyterhub' in sys.modules:
     from traitlets.config import MultipleInstanceError
+
     from jupyterhub.app import JupyterHub
 
     app = None

jupyterhub/alembic/versions/19c0846f6344_base_revision_for_0_5.py

@@ -11,8 +11,8 @@ down_revision = None
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 
 def upgrade():

jupyterhub/alembic/versions/1cebaf56856c_session_id.py

@@ -15,8 +15,8 @@ import logging
 
 logger = logging.getLogger('alembic')
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 tables = ('oauth_access_tokens', 'oauth_codes')
 

jupyterhub/alembic/versions/3ec6993fe20c_encrypted_auth_state.py

@@ -22,8 +22,9 @@ import logging
 
 logger = logging.getLogger('alembic')
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
+
 from jupyterhub.orm import JSONDict
 
 

jupyterhub/alembic/versions/4dc2d5a8c53c_user_options.py

@@ -11,8 +11,9 @@ down_revision = '896818069c98'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
+
 from jupyterhub.orm import JSONDict
 
 

jupyterhub/alembic/versions/56cc5a70207e_token_tracking.py

@@ -11,11 +11,11 @@ down_revision = '1cebaf56856c'
 branch_labels = None
 depends_on = None
 
-from alembic import op
-import sqlalchemy as sa
-
 import logging
 
+import sqlalchemy as sa
+from alembic import op
+
 logger = logging.getLogger('alembic')
 
 

jupyterhub/alembic/versions/651f5419b74d_api_token_scopes.py

@@ -13,17 +13,12 @@ depends_on = None
 
 import sqlalchemy as sa
 from alembic import op
-from sqlalchemy import Column
+from sqlalchemy import Column, ForeignKey, Integer, Table, Unicode
-from sqlalchemy import ForeignKey
-from sqlalchemy import Integer
-from sqlalchemy import Table
-from sqlalchemy import Unicode
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import relationship
 from sqlalchemy.orm.session import Session
 
-from jupyterhub import orm
+from jupyterhub import orm, roles
-from jupyterhub import roles
 
 
 def upgrade():

jupyterhub/alembic/versions/833da8570507_rbac.py

@@ -12,12 +12,11 @@ down_revision = '4dc2d5a8c53c'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 from jupyterhub import orm
 
-
 naming_convention = orm.meta.naming_convention
 
 

jupyterhub/alembic/versions/896818069c98_token_expires.py

@@ -11,8 +11,8 @@ down_revision = 'd68c98b66cd4'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 
 def upgrade():

jupyterhub/alembic/versions/99a28a4418e1_user_created.py

@@ -12,11 +12,11 @@ branch_labels = None
 depends_on = None
 
 
-from alembic import op
-import sqlalchemy as sa
-
 from datetime import datetime
 
+import sqlalchemy as sa
+from alembic import op
+
 
 def upgrade():
     op.add_column('users', sa.Column('created', sa.DateTime, nullable=True))

jupyterhub/alembic/versions/af4cbdb2d13c_services.py

@@ -11,8 +11,8 @@ down_revision = 'eeb276e51423'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 
 def upgrade():

jupyterhub/alembic/versions/d68c98b66cd4_client_description.py

@@ -11,8 +11,8 @@ down_revision = '99a28a4418e1'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
 
 
 def upgrade():

jupyterhub/alembic/versions/eeb276e51423_auth_state.py

@@ -12,8 +12,9 @@ down_revision = '19c0846f6344'
 branch_labels = None
 depends_on = None
 
-from alembic import op
 import sqlalchemy as sa
+from alembic import op
+
 from jupyterhub.orm import JSONDict
 
 

jupyterhub/apihandlers/__init__.py

@@ -1,9 +1,4 @@
-from . import auth
+from . import auth, groups, hub, proxy, services, users
-from . import groups
-from . import hub
-from . import proxy
-from . import services
-from . import users
 from .base import *
 
 default_handlers = []

jupyterhub/apihandlers/auth.py

@@ -4,22 +4,14 @@
 import itertools
 import json
 from datetime import datetime
-from urllib.parse import parse_qsl
+from urllib.parse import parse_qsl, quote, urlencode, urlparse, urlunparse
-from urllib.parse import quote
-from urllib.parse import urlencode
-from urllib.parse import urlparse
-from urllib.parse import urlunparse
 
 from oauthlib import oauth2
 from tornado import web
 
-from .. import orm
+from .. import orm, roles, scopes
-from .. import roles
+from ..utils import get_browser_protocol, token_authenticated
-from .. import scopes
+from .base import APIHandler, BaseHandler
-from ..utils import get_browser_protocol
-from ..utils import token_authenticated
-from .base import APIHandler
-from .base import BaseHandler
 
 
 class TokenAPIHandler(APIHandler):

jupyterhub/apihandlers/base.py

@@ -4,10 +4,7 @@
 import json
 from functools import lru_cache
 from http.client import responses
-from urllib.parse import parse_qs
+from urllib.parse import parse_qs, urlencode, urlparse, urlunparse
-from urllib.parse import urlencode
-from urllib.parse import urlparse
-from urllib.parse import urlunparse
 
 from sqlalchemy.exc import SQLAlchemyError
 from tornado import web
@@ -15,9 +12,7 @@ from tornado import web
 from .. import orm
 from ..handlers import BaseHandler
 from ..scopes import get_scopes_for
-from ..utils import get_browser_protocol
+from ..utils import get_browser_protocol, isoformat, url_path_join
-from ..utils import isoformat
-from ..utils import url_path_join
 
 PAGINATION_MEDIA_TYPE = "application/jupyterhub-pagination+json"
 

jupyterhub/apihandlers/groups.py

@@ -6,8 +6,7 @@ import json
 from tornado import web
 
 from .. import orm
-from ..scopes import needs_scope
+from ..scopes import Scope, needs_scope
-from ..scopes import Scope
 from .base import APIHandler
 
 

jupyterhub/apihandlers/services.py

@@ -6,8 +6,7 @@ Currently GET-only, no actions can be taken to modify services.
 # Distributed under the terms of the Modified BSD License.
 import json
 
-from ..scopes import needs_scope
+from ..scopes import Scope, needs_scope
-from ..scopes import Scope
 from .base import APIHandler
 
 

jupyterhub/apihandlers/users.py

@@ -3,26 +3,19 @@
 # Distributed under the terms of the Modified BSD License.
 import asyncio
 import json
-from datetime import datetime
+from datetime import datetime, timedelta, timezone
-from datetime import timedelta
-from datetime import timezone
 
 from async_generator import aclosing
 from dateutil.parser import parse as parse_date
-from sqlalchemy import func
+from sqlalchemy import func, or_
-from sqlalchemy import or_
 from tornado import web
 from tornado.iostream import StreamClosedError
 
-from .. import orm
+from .. import orm, scopes
-from .. import scopes
 from ..roles import assign_default_roles
 from ..scopes import needs_scope
 from ..user import User
-from ..utils import isoformat
+from ..utils import isoformat, iterate_until, maybe_future, url_path_join
-from ..utils import iterate_until
-from ..utils import maybe_future
-from ..utils import url_path_join
 from .base import APIHandler
 
 

jupyterhub/app.py

@@ -14,15 +14,11 @@ import socket
 import sys
 import time
 from concurrent.futures import ThreadPoolExecutor
-from datetime import datetime
+from datetime import datetime, timedelta, timezone
-from datetime import timedelta
-from datetime import timezone
 from getpass import getuser
 from operator import itemgetter
 from textwrap import dedent
-from urllib.parse import unquote
+from urllib.parse import unquote, urlparse, urlunparse
-from urllib.parse import urlparse
-from urllib.parse import urlunparse
 
 if sys.version_info[:2] < (3, 3):
     raise ValueError("Python < 3.3 not supported: %s" % sys.version)
@@ -36,78 +32,72 @@ except AttributeError as e:
     asyncio_all_tasks = asyncio.Task.all_tasks
     asyncio_current_task = asyncio.Task.current_task
 
-from dateutil.parser import parse as parse_date
-from jinja2 import Environment, FileSystemLoader, PrefixLoader, ChoiceLoader
-from sqlalchemy.exc import OperationalError, SQLAlchemyError
-
-from tornado.httpclient import AsyncHTTPClient
 import tornado.httpserver
-from tornado.ioloop import IOLoop, PeriodicCallback
-from tornado.log import app_log, access_log, gen_log
 import tornado.options
+from dateutil.parser import parse as parse_date
+from jinja2 import ChoiceLoader, Environment, FileSystemLoader, PrefixLoader
+from jupyter_telemetry.eventlog import EventLog
+from sqlalchemy.exc import OperationalError, SQLAlchemyError
 from tornado import gen, web
-
+from tornado.httpclient import AsyncHTTPClient
+from tornado.ioloop import IOLoop, PeriodicCallback
+from tornado.log import access_log, app_log, gen_log
 from traitlets import (
-    Unicode,
-    Integer,
-    Dict,
-    List,
-    Bool,
     Any,
-    Tuple,
+    Bool,
-    Set,
-    Instance,
     Bytes,
+    Dict,
     Float,
+    Instance,
+    Integer,
+    List,
+    Set,
+    Tuple,
+    Unicode,
     Union,
-    observe,
     default,
+    observe,
     validate,
 )
 from traitlets.config import Application, Configurable, catch_config_error
 
-from jupyter_telemetry.eventlog import EventLog
-
 here = os.path.dirname(__file__)
 
 import jupyterhub
-from . import handlers, apihandlers
-from .handlers.static import CacheControlStaticFilesHandler, LogoHandler
-from .services.service import Service
 
-from . import crypto
+from . import apihandlers, crypto, dbutil, handlers, orm, roles, scopes
-from . import dbutil
-from . import orm
-from . import roles
-from . import scopes
-from .user import UserDict
-from .oauth.provider import make_provider
 from ._data import DATA_FILES_PATH
-from .log import CoroutineLogFormatter, log_request
-from .proxy import Proxy, ConfigurableHTTPProxy
-from .traitlets import URLPrefix, Command, EntryPointType, Callable
-from .utils import (
-    AnyTimeoutError,
-    catch_db_error,
-    maybe_future,
-    url_path_join,
-    print_stacks,
-    print_ps_info,
-    make_ssl_context,
-)
-from .metrics import HUB_STARTUP_DURATION_SECONDS
-from .metrics import INIT_SPAWNERS_DURATION_SECONDS
-from .metrics import RUNNING_SERVERS
-from .metrics import TOTAL_USERS
 
 # classes for config
 from .auth import Authenticator, PAMAuthenticator
 from .crypto import CryptKeeper
-from .spawner import Spawner, LocalProcessSpawner
-from .objects import Hub, Server
 
 # For faking stats
 from .emptyclass import EmptyClass
+from .handlers.static import CacheControlStaticFilesHandler, LogoHandler
+from .log import CoroutineLogFormatter, log_request
+from .metrics import (
+    HUB_STARTUP_DURATION_SECONDS,
+    INIT_SPAWNERS_DURATION_SECONDS,
+    RUNNING_SERVERS,
+    TOTAL_USERS,
+)
+from .oauth.provider import make_provider
+from .objects import Hub, Server
+from .proxy import ConfigurableHTTPProxy, Proxy
+from .services.service import Service
+from .spawner import LocalProcessSpawner, Spawner
+from .traitlets import Callable, Command, EntryPointType, URLPrefix
+from .user import UserDict
+from .utils import (
+    AnyTimeoutError,
+    catch_db_error,
+    make_ssl_context,
+    maybe_future,
+    print_ps_info,
+    print_stacks,
+    url_path_join,
+)
 
 common_aliases = {
     'log-level': 'Application.log_level',

jupyterhub/auth.py

@@ -9,9 +9,7 @@ import warnings
 from concurrent.futures import ThreadPoolExecutor
 from functools import partial
 from shutil import which
-from subprocess import PIPE
+from subprocess import PIPE, STDOUT, Popen
-from subprocess import Popen
-from subprocess import STDOUT
 
 try:
     import pamela
@@ -20,13 +18,12 @@ except Exception as e:
     _pamela_error = e
 
 from tornado.concurrent import run_on_executor
-
+from traitlets import Any, Bool, Dict, Integer, Set, Unicode, default, observe
 from traitlets.config import LoggingConfigurable
-from traitlets import Bool, Integer, Set, Unicode, Dict, Any, default, observe
 
 from .handlers.login import LoginHandler
-from .utils import maybe_future, url_path_join
 from .traitlets import Command
+from .utils import maybe_future, url_path_join
 
 
 class Authenticator(LoggingConfigurable):

jupyterhub/crypto.py

@@ -4,18 +4,12 @@ import os
 from binascii import a2b_hex
 from concurrent.futures import ThreadPoolExecutor
 
-from traitlets import Any
+from traitlets import Any, Integer, List, default, observe, validate
-from traitlets import default
+from traitlets.config import Config, SingletonConfigurable
-from traitlets import Integer
-from traitlets import List
-from traitlets import observe
-from traitlets import validate
-from traitlets.config import Config
-from traitlets.config import SingletonConfigurable
 
 try:
     import cryptography
-    from cryptography.fernet import Fernet, MultiFernet, InvalidToken
+    from cryptography.fernet import Fernet, InvalidToken, MultiFernet
 except ImportError:
     cryptography = None
 

jupyterhub/handlers/__init__.py

@@ -1,7 +1,4 @@
-from . import base
+from . import base, login, metrics, pages
-from . import login
-from . import metrics
-from . import pages
 from .base import *
 from .login import *
 

jupyterhub/handlers/base.py

@@ -9,50 +9,43 @@ import random
 import re
 import time
 import uuid
-from datetime import datetime
+from datetime import datetime, timedelta
-from datetime import timedelta
 from http.client import responses
-from urllib.parse import parse_qs
+from urllib.parse import parse_qs, parse_qsl, urlencode, urlparse, urlunparse
-from urllib.parse import parse_qsl
-from urllib.parse import urlencode
-from urllib.parse import urlparse
-from urllib.parse import urlunparse
 
 from jinja2 import TemplateNotFound
 from sqlalchemy.exc import SQLAlchemyError
-from tornado import gen
+from tornado import gen, web
-from tornado import web
+from tornado.httputil import HTTPHeaders, url_concat
-from tornado.httputil import HTTPHeaders
-from tornado.httputil import url_concat
 from tornado.ioloop import IOLoop
 from tornado.log import app_log
-from tornado.web import addslash
+from tornado.web import RequestHandler, addslash
-from tornado.web import RequestHandler
 
-from .. import __version__
+from .. import __version__, orm, roles, scopes
-from .. import orm
+from ..metrics import (
-from .. import roles
+    PROXY_ADD_DURATION_SECONDS,
-from .. import scopes
+    PROXY_DELETE_DURATION_SECONDS,
-from ..metrics import PROXY_ADD_DURATION_SECONDS
+    RUNNING_SERVERS,
-from ..metrics import PROXY_DELETE_DURATION_SECONDS
+    SERVER_POLL_DURATION_SECONDS,
-from ..metrics import ProxyDeleteStatus
+    SERVER_SPAWN_DURATION_SECONDS,
-from ..metrics import RUNNING_SERVERS
+    SERVER_STOP_DURATION_SECONDS,
-from ..metrics import SERVER_POLL_DURATION_SECONDS
+    TOTAL_USERS,
-from ..metrics import SERVER_SPAWN_DURATION_SECONDS
+    ProxyDeleteStatus,
-from ..metrics import SERVER_STOP_DURATION_SECONDS
+    ServerPollStatus,
-from ..metrics import ServerPollStatus
+    ServerSpawnStatus,
-from ..metrics import ServerSpawnStatus
+    ServerStopStatus,
-from ..metrics import ServerStopStatus
+)
-from ..metrics import TOTAL_USERS
 from ..objects import Server
 from ..scopes import needs_scope
 from ..spawner import LocalProcessSpawner
 from ..user import User
-from ..utils import AnyTimeoutError
+from ..utils import (
-from ..utils import get_accepted_mimetype
+    AnyTimeoutError,
-from ..utils import get_browser_protocol
+    get_accepted_mimetype,
-from ..utils import maybe_future
+    get_browser_protocol,
-from ..utils import url_path_join
+    maybe_future,
+    url_path_join,
+)
 
 # pattern for the authentication token header
 auth_header_pat = re.compile(r'^(?:token|bearer)\s+([^\s]+)$', flags=re.IGNORECASE)

jupyterhub/handlers/metrics.py

@@ -1,7 +1,5 @@
 """Handlers for serving prometheus metrics"""
-from prometheus_client import CONTENT_TYPE_LATEST
+from prometheus_client import CONTENT_TYPE_LATEST, REGISTRY, generate_latest
-from prometheus_client import generate_latest
-from prometheus_client import REGISTRY
 
 from ..utils import metrics_authentication
 from .base import BaseHandler

jupyterhub/handlers/pages.py

@@ -12,11 +12,9 @@ from tornado import web
 from tornado.httputil import url_concat
 
 from .. import __version__
-from ..metrics import SERVER_POLL_DURATION_SECONDS
+from ..metrics import SERVER_POLL_DURATION_SECONDS, ServerPollStatus
-from ..metrics import ServerPollStatus
 from ..scopes import needs_scope
-from ..utils import maybe_future
+from ..utils import maybe_future, url_path_join
-from ..utils import url_path_join
 from .base import BaseHandler
 
 

jupyterhub/log.py

@@ -6,13 +6,10 @@ import logging
 import traceback
 from functools import partial
 from http.cookies import SimpleCookie
-from urllib.parse import urlparse
+from urllib.parse import urlparse, urlunparse
-from urllib.parse import urlunparse
 
-from tornado.log import access_log
+from tornado.log import LogFormatter, access_log
-from tornado.log import LogFormatter
+from tornado.web import HTTPError, StaticFileHandler
-from tornado.web import HTTPError
-from tornado.web import StaticFileHandler
 
 from .handlers.pages import HealthCheckHandler
 from .metrics import prometheus_log_method

jupyterhub/metrics.py

@@ -21,8 +21,7 @@ them manually here.
 """
 from enum import Enum
 
-from prometheus_client import Gauge
+from prometheus_client import Gauge, Histogram
-from prometheus_client import Histogram
 
 REQUEST_DURATION_SECONDS = Histogram(
     'jupyterhub_request_duration_seconds',

jupyterhub/oauth/provider.py

@@ -3,19 +3,14 @@
 implements https://oauthlib.readthedocs.io/en/latest/oauth2/server.html
 """
 from oauthlib import uri_validate
-from oauthlib.oauth2 import RequestValidator
+from oauthlib.oauth2 import RequestValidator, WebApplicationServer
-from oauthlib.oauth2 import WebApplicationServer
+from oauthlib.oauth2.rfc6749.grant_types import authorization_code, base
-from oauthlib.oauth2.rfc6749.grant_types import authorization_code
-from oauthlib.oauth2.rfc6749.grant_types import base
 from tornado.log import app_log
 
 from .. import orm
 from ..roles import roles_to_scopes
-from ..scopes import _check_scopes_exist
+from ..scopes import _check_scopes_exist, access_scopes, identify_scopes
-from ..scopes import access_scopes
+from ..utils import compare_token, hash_token
-from ..scopes import identify_scopes
-from ..utils import compare_token
-from ..utils import hash_token
 
 # patch absolute-uri check
 # because we want to allow relative uri oauth

jupyterhub/objects.py

@@ -3,25 +3,20 @@
 # Distributed under the terms of the Modified BSD License.
 import socket
 import warnings
-from urllib.parse import urlparse
+from urllib.parse import urlparse, urlunparse
-from urllib.parse import urlunparse
 
-from traitlets import default
+from traitlets import HasTraits, Instance, Integer, Unicode, default, observe, validate
-from traitlets import HasTraits
-from traitlets import Instance
-from traitlets import Integer
-from traitlets import observe
-from traitlets import Unicode
-from traitlets import validate
 
 from . import orm
 from .traitlets import URLPrefix
-from .utils import can_connect
+from .utils import (
-from .utils import make_ssl_context
+    can_connect,
-from .utils import random_port
+    make_ssl_context,
-from .utils import url_path_join
+    random_port,
-from .utils import wait_for_http_server
+    url_path_join,
-from .utils import wait_for_server
+    wait_for_http_server,
+    wait_for_server,
+)
 
 
 class Server(HasTraits):

jupyterhub/orm.py

@@ -3,47 +3,44 @@
 # Distributed under the terms of the Modified BSD License.
 import enum
 import json
-from base64 import decodebytes
+from base64 import decodebytes, encodebytes
-from base64 import encodebytes
+from datetime import datetime, timedelta
-from datetime import datetime
-from datetime import timedelta
 
 import alembic.command
 import alembic.config
 from alembic.script import ScriptDirectory
-from sqlalchemy import Boolean
+from sqlalchemy import (
-from sqlalchemy import Column
+    Boolean,
-from sqlalchemy import create_engine
+    Column,
-from sqlalchemy import DateTime
+    DateTime,
-from sqlalchemy import event
+    ForeignKey,
-from sqlalchemy import exc
+    Integer,
-from sqlalchemy import ForeignKey
+    MetaData,
-from sqlalchemy import inspect
+    Table,
-from sqlalchemy import Integer
+    Unicode,
-from sqlalchemy import MetaData
+    create_engine,
-from sqlalchemy import or_
+    event,
-from sqlalchemy import select
+    exc,
-from sqlalchemy import Table
+    inspect,
-from sqlalchemy import Unicode
+    or_,
+    select,
+)
 from sqlalchemy.ext.declarative import declarative_base
-from sqlalchemy.orm import backref
+from sqlalchemy.orm import (
-from sqlalchemy.orm import interfaces
+    Session,
-from sqlalchemy.orm import object_session
+    backref,
-from sqlalchemy.orm import relationship
+    interfaces,
-from sqlalchemy.orm import Session
+    object_session,
-from sqlalchemy.orm import sessionmaker
+    relationship,
+    sessionmaker,
+)
 from sqlalchemy.pool import StaticPool
 from sqlalchemy.sql.expression import bindparam
-from sqlalchemy.types import LargeBinary
+from sqlalchemy.types import LargeBinary, Text, TypeDecorator
-from sqlalchemy.types import Text
-from sqlalchemy.types import TypeDecorator
 from tornado.log import app_log
 
 from .roles import roles_to_scopes
-from .utils import compare_token
+from .utils import compare_token, hash_token, new_token, random_port
-from .utils import hash_token
-from .utils import new_token
-from .utils import random_port
 
 # top-level variable for easier mocking in tests
 utcnow = datetime.utcnow

jupyterhub/proxy.py

@@ -26,29 +26,18 @@ from subprocess import Popen
 from urllib.parse import quote
 from weakref import WeakKeyDictionary
 
-from tornado.httpclient import AsyncHTTPClient
+from tornado.httpclient import AsyncHTTPClient, HTTPError, HTTPRequest
-from tornado.httpclient import HTTPError
-from tornado.httpclient import HTTPRequest
 from tornado.ioloop import PeriodicCallback
-from traitlets import Any
+from traitlets import Any, Bool, Dict, Instance, Integer, Unicode, default, observe
-from traitlets import Bool
-from traitlets import default
-from traitlets import Dict
-from traitlets import Instance
-from traitlets import Integer
-from traitlets import observe
-from traitlets import Unicode
 from traitlets.config import LoggingConfigurable
 
-from . import utils
-from .metrics import CHECK_ROUTES_DURATION_SECONDS
-from .metrics import PROXY_POLL_DURATION_SECONDS
-from .objects import Server
-from .utils import AnyTimeoutError
-from .utils import exponential_backoff
-from .utils import url_path_join
 from jupyterhub.traitlets import Command
 
+from . import utils
+from .metrics import CHECK_ROUTES_DURATION_SECONDS, PROXY_POLL_DURATION_SECONDS
+from .objects import Server
+from .utils import AnyTimeoutError, exponential_backoff, url_path_join
+
 
 def _one_at_a_time(method):
     """decorator to limit an async method to be called only once

jupyterhub/roles.py

@@ -7,8 +7,7 @@ from functools import wraps
 from sqlalchemy import func
 from tornado.log import app_log
 
-from . import orm
+from . import orm, scopes
-from . import scopes
 
 
 def get_default_roles():

jupyterhub/scopes.py

@@ -23,8 +23,7 @@ import sqlalchemy as sa
 from tornado import web
 from tornado.log import app_log
 
-from . import orm
+from . import orm, roles
-from . import roles
 
 """when modifying the scope definitions, make sure that `docs/source/rbac/generate-scope-table.py` is run
    so that changes are reflected in the documentation and REST API description."""

jupyterhub/services/auth.py

@@ -40,21 +40,12 @@ from urllib.parse import urlencode
 import requests
 from tornado.httputil import url_concat
 from tornado.log import app_log
-from tornado.web import HTTPError
+from tornado.web import HTTPError, RequestHandler
-from tornado.web import RequestHandler
+from traitlets import Dict, Instance, Integer, Set, Unicode, default, observe, validate
-from traitlets import default
-from traitlets import Dict
-from traitlets import Instance
-from traitlets import Integer
-from traitlets import observe
-from traitlets import Set
-from traitlets import Unicode
-from traitlets import validate
 from traitlets.config import SingletonConfigurable
 
 from ..scopes import _intersect_expanded_scopes
-from ..utils import get_browser_protocol
+from ..utils import get_browser_protocol, url_path_join
-from ..utils import url_path_join
 
 
 def check_scopes(required_scopes, scopes):

jupyterhub/services/service.py

@@ -45,21 +45,22 @@ import pipes
 import shutil
 from subprocess import Popen
 
-from traitlets import Any
+from traitlets import (
-from traitlets import Bool
+    Any,
-from traitlets import default
+    Bool,
-from traitlets import Dict
+    Dict,
-from traitlets import HasTraits
+    HasTraits,
-from traitlets import Instance
+    Instance,
-from traitlets import List
+    List,
-from traitlets import Unicode
+    Unicode,
-from traitlets import validate
+    default,
+    validate,
+)
 from traitlets.config import LoggingConfigurable
 
 from .. import orm
 from ..objects import Server
-from ..spawner import LocalProcessSpawner
+from ..spawner import LocalProcessSpawner, set_user_setuid
-from ..spawner import set_user_setuid
 from ..traitlets import Command
 from ..utils import url_path_join
 

jupyterhub/singleuser/__init__.py

@@ -2,10 +2,8 @@
 
 Contains default notebook-app subclass and mixins
 """
-from .app import main
+from .app import SingleUserNotebookApp, main
-from .app import SingleUserNotebookApp
+from .mixins import HubAuthenticatedHandler, make_singleuser_app
-from .mixins import HubAuthenticatedHandler
-from .mixins import make_singleuser_app
 
 # backward-compatibility
 JupyterHubLoginHandler = SingleUserNotebookApp.login_handler_class

jupyterhub/singleuser/mixins.py

@@ -21,35 +21,29 @@ from importlib import import_module
 from textwrap import dedent
 from urllib.parse import urlparse
 
-from jinja2 import ChoiceLoader
+from jinja2 import ChoiceLoader, FunctionLoader
-from jinja2 import FunctionLoader
 from tornado import ioloop
-from tornado.httpclient import AsyncHTTPClient
+from tornado.httpclient import AsyncHTTPClient, HTTPRequest
-from tornado.httpclient import HTTPRequest
 from tornado.web import RequestHandler
-from traitlets import Any
+from traitlets import (
-from traitlets import Bool
+    Any,
-from traitlets import Bytes
+    Bool,
-from traitlets import CUnicode
+    Bytes,
-from traitlets import default
+    CUnicode,
-from traitlets import import_item
+    Integer,
-from traitlets import Integer
+    TraitError,
-from traitlets import observe
+    Unicode,
-from traitlets import TraitError
+    default,
-from traitlets import Unicode
+    import_item,
-from traitlets import validate
+    observe,
+    validate,
+)
 from traitlets.config import Configurable
 
-from .._version import __version__
+from .._version import __version__, _check_version
-from .._version import _check_version
 from ..log import log_request
-from ..services.auth import HubOAuth
+from ..services.auth import HubOAuth, HubOAuthCallbackHandler, HubOAuthenticated
-from ..services.auth import HubOAuthCallbackHandler
+from ..utils import exponential_backoff, isoformat, make_ssl_context, url_path_join
-from ..services.auth import HubOAuthenticated
-from ..utils import exponential_backoff
-from ..utils import isoformat
-from ..utils import make_ssl_context
-from ..utils import url_path_join
 
 
 def _bool_env(key):

jupyterhub/spawner.py

@@ -19,29 +19,31 @@ from urllib.parse import urlparse
 from async_generator import aclosing
 from sqlalchemy import inspect
 from tornado.ioloop import PeriodicCallback
-from traitlets import Any
+from traitlets import (
-from traitlets import Bool
+    Any,
-from traitlets import default
+    Bool,
-from traitlets import Dict
+    Dict,
-from traitlets import Float
+    Float,
-from traitlets import Instance
+    Instance,
-from traitlets import Integer
+    Integer,
-from traitlets import List
+    List,
-from traitlets import observe
+    Unicode,
-from traitlets import Unicode
+    Union,
-from traitlets import Union
+    default,
-from traitlets import validate
+    observe,
+    validate,
+)
 from traitlets.config import LoggingConfigurable
 
 from .objects import Server
-from .traitlets import ByteSpecification
+from .traitlets import ByteSpecification, Callable, Command
-from .traitlets import Callable
+from .utils import (
-from .traitlets import Command
+    AnyTimeoutError,
-from .utils import AnyTimeoutError
+    exponential_backoff,
-from .utils import exponential_backoff
+    maybe_future,
-from .utils import maybe_future
+    random_port,
-from .utils import random_port
+    url_path_join,
-from .utils import url_path_join
+)
 
 if os.name == 'nt':
     import psutil

jupyterhub/tests/conftest.py

@@ -35,22 +35,17 @@ from getpass import getuser
 from subprocess import TimeoutExpired
 from unittest import mock
 
-from pytest import fixture
+from pytest import fixture, raises
-from pytest import raises
 from tornado import ioloop
 from tornado.httpclient import HTTPError
 from tornado.platform.asyncio import AsyncIOMainLoop
 
 import jupyterhub.services.service
-from . import mocking
+
-from .. import crypto
+from .. import crypto, orm, scopes
-from .. import orm
+from ..roles import create_role, get_default_roles, mock_roles, update_roles
-from .. import scopes
-from ..roles import create_role
-from ..roles import get_default_roles
-from ..roles import mock_roles
-from ..roles import update_roles
 from ..utils import random_port
+from . import mocking
 from .mocking import MockHub
 from .test_services import mockservice_cmd
 from .utils import add_user

jupyterhub/tests/mocking.py

@@ -37,23 +37,15 @@ from urllib.parse import urlparse
 
 from pamela import PAMError
 from tornado.ioloop import IOLoop
-from traitlets import Bool
+from traitlets import Bool, Dict, default
-from traitlets import default
-from traitlets import Dict
 
-from .. import metrics
+from .. import metrics, orm, roles
-from .. import orm
-from .. import roles
 from ..app import JupyterHub
 from ..auth import PAMAuthenticator
 from ..singleuser import SingleUserNotebookApp
 from ..spawner import SimpleLocalProcessSpawner
-from ..utils import random_port
+from ..utils import random_port, utcnow
-from ..utils import utcnow
+from .utils import async_requests, public_host, public_url, ssl_setup
-from .utils import async_requests
-from .utils import public_host
-from .utils import public_url
-from .utils import ssl_setup
 
 
 def mock_authenticate(username, password, service, encoding):

jupyterhub/tests/mockservice.py

@@ -19,15 +19,14 @@ import sys
 from urllib.parse import urlparse
 
 import requests
-from tornado import httpserver
+from tornado import httpserver, ioloop, log, web
-from tornado import ioloop
-from tornado import log
-from tornado import web
 from tornado.httputil import url_concat
 
-from jupyterhub.services.auth import HubAuthenticated
+from jupyterhub.services.auth import (
-from jupyterhub.services.auth import HubOAuthCallbackHandler
+    HubAuthenticated,
-from jupyterhub.services.auth import HubOAuthenticated
+    HubOAuthCallbackHandler,
+    HubOAuthenticated,
+)
 from jupyterhub.utils import make_ssl_context
 
 
@@ -123,7 +122,7 @@ def main():
 
 
 if __name__ == '__main__':
-    from tornado.options import parse_command_line, options
+    from tornado.options import options, parse_command_line
 
     parse_command_line()
     options.logging = 'debug'

jupyterhub/tests/mocksu.py

@@ -16,10 +16,7 @@ import os
 import sys
 from urllib.parse import urlparse
 
-from tornado import httpserver
+from tornado import httpserver, ioloop, log, web
-from tornado import ioloop
-from tornado import log
-from tornado import web
 from tornado.options import options
 
 from ..utils import make_ssl_context

jupyterhub/tests/test_api.py

@@ -4,32 +4,23 @@ import json
 import re
 import sys
 import uuid
-from datetime import datetime
+from datetime import datetime, timedelta
-from datetime import timedelta
 from unittest import mock
-from urllib.parse import quote
+from urllib.parse import quote, urlparse, urlunparse
-from urllib.parse import urlparse
-from urllib.parse import urlunparse
 
-from pytest import fixture
+from pytest import fixture, mark
-from pytest import mark
 from tornado.httputil import url_concat
 
 import jupyterhub
+
 from .. import orm
 from ..apihandlers.base import PAGINATION_MEDIA_TYPE
 from ..objects import Server
 from ..utils import url_path_join as ujoin
 from ..utils import utcnow
 from .conftest import new_username
-from .mocking import public_host
+from .mocking import public_host, public_url
-from .mocking import public_url
+from .utils import add_user, api_request, async_requests, auth_header, find_user
-from .utils import add_user
-from .utils import api_request
-from .utils import async_requests
-from .utils import auth_header
-from .utils import find_user
-
 
 # --------------------
 # Authentication tests

jupyterhub/tests/test_app.py

@@ -6,11 +6,8 @@ import os
 import re
 import sys
 import time
-from subprocess import check_output
+from subprocess import PIPE, Popen, check_output
-from subprocess import PIPE
+from tempfile import NamedTemporaryFile, TemporaryDirectory
-from subprocess import Popen
-from tempfile import NamedTemporaryFile
-from tempfile import TemporaryDirectory
 from unittest.mock import patch
 
 import pytest
@@ -18,8 +15,7 @@ import traitlets
 from traitlets.config import Config
 
 from .. import orm
-from ..app import COOKIE_SECRET_BYTES
+from ..app import COOKIE_SECRET_BYTES, JupyterHub
-from ..app import JupyterHub
 from .mocking import MockHub
 from .test_api import add_user
 

jupyterhub/tests/test_auth.py

@@ -10,16 +10,10 @@ from requests import HTTPError
 from traitlets import Any
 from traitlets.config import Config
 
-from .mocking import MockPAMAuthenticator
+from jupyterhub import auth, crypto, orm
-from .mocking import MockStructGroup
+
-from .mocking import MockStructPasswd
+from .mocking import MockPAMAuthenticator, MockStructGroup, MockStructPasswd
-from .utils import add_user
+from .utils import add_user, async_requests, get_page, public_url
-from .utils import async_requests
-from .utils import get_page
-from .utils import public_url
-from jupyterhub import auth
-from jupyterhub import crypto
-from jupyterhub import orm
 
 
 async def test_pam_auth():

jupyterhub/tests/test_auth_expiry.py

@@ -9,13 +9,11 @@ authentication can expire in a number of ways:
 """
 from contextlib import contextmanager
 from unittest import mock
-from urllib.parse import parse_qs
+from urllib.parse import parse_qs, urlparse
-from urllib.parse import urlparse
 
 import pytest
 
-from .utils import api_request
+from .utils import api_request, get_page
-from .utils import get_page
 
 
 async def refresh_expired(authenticator, user):

jupyterhub/tests/test_crypto.py

@@ -1,13 +1,11 @@
 import os
-from binascii import b2a_base64
+from binascii import b2a_base64, b2a_hex
-from binascii import b2a_hex
 from unittest.mock import patch
 
 import pytest
 
 from .. import crypto
-from ..crypto import decrypt
+from ..crypto import decrypt, encrypt
-from ..crypto import encrypt
 
 keys = [('%i' % i).encode('ascii') * 32 for i in range(3)]
 hex_keys = [b2a_hex(key).decode('ascii') for key in keys]

jupyterhub/tests/test_db.py

@@ -9,8 +9,7 @@ from pytest import raises
 from traitlets.config import Config
 
 from .. import orm
-from ..app import NewToken
+from ..app import NewToken, UpgradeDB
-from ..app import UpgradeDB
 from ..scopes import _check_scopes_exist
 
 here = os.path.abspath(os.path.dirname(__file__))

jupyterhub/tests/test_eventlog.py

@@ -16,7 +16,6 @@ from traitlets.config import Config
 
 from .mocking import MockHub
 
-
 # To test new schemas, add them to the `valid_events`
 # and `invalid_events` dictionary below.
 

jupyterhub/tests/test_internal_ssl_connections.py

@@ -4,8 +4,7 @@ import time
 from unittest import mock
 
 import pytest
-from requests.exceptions import ConnectionError
+from requests.exceptions import ConnectionError, SSLError
-from requests.exceptions import SSLError
 
 from ..utils import AnyTimeoutError
 from .test_api import add_user

jupyterhub/tests/test_metrics.py

@@ -3,11 +3,9 @@ from unittest import mock
 
 import pytest
 
-from .utils import api_request
+from jupyterhub import metrics, orm, roles
-from .utils import get_page
+
-from jupyterhub import metrics
+from .utils import api_request, get_page
-from jupyterhub import orm
-from jupyterhub import roles
 
 
 async def test_total_users(app):

jupyterhub/tests/test_named_servers.py

@@ -2,22 +2,15 @@
 import asyncio
 import json
 from unittest import mock
-from urllib.parse import urlencode
+from urllib.parse import urlencode, urlparse
-from urllib.parse import urlparse
 
 import pytest
 from tornado.httputil import url_concat
 
 from ..utils import url_path_join
-from .mocking import FormSpawner
+from .mocking import FormSpawner, public_url
-from .mocking import public_url
+from .test_api import TIMESTAMP, add_user, api_request, fill_user, normalize_user
-from .test_api import add_user
+from .utils import async_requests, get_page
-from .test_api import api_request
-from .test_api import fill_user
-from .test_api import normalize_user
-from .test_api import TIMESTAMP
-from .utils import async_requests
-from .utils import get_page
 
 
 @pytest.fixture

jupyterhub/tests/test_orm.py

@@ -3,17 +3,13 @@
 # Distributed under the terms of the Modified BSD License.
 import os
 import socket
-from datetime import datetime
+from datetime import datetime, timedelta
-from datetime import timedelta
 from unittest import mock
 
 import pytest
 from tornado import gen
 
-from .. import crypto
+from .. import crypto, objects, orm, roles
-from .. import objects
-from .. import orm
-from .. import roles
 from ..emptyclass import EmptyClass
 from ..user import User
 from .mocking import MockSpawner

jupyterhub/tests/test_pages.py

@@ -2,31 +2,28 @@
 import asyncio
 import sys
 from unittest import mock
-from urllib.parse import parse_qs
+from urllib.parse import parse_qs, urlencode, urlparse
-from urllib.parse import urlencode
-from urllib.parse import urlparse
 
 import pytest
 from bs4 import BeautifulSoup
 from tornado.escape import url_escape
 from tornado.httputil import url_concat
 
-from .. import orm
+from .. import orm, roles, scopes
-from .. import roles
-from .. import scopes
 from ..auth import Authenticator
 from ..handlers import BaseHandler
 from ..utils import url_path_join
 from ..utils import url_path_join as ujoin
-from .mocking import FalsyCallableFormSpawner
+from .mocking import FalsyCallableFormSpawner, FormSpawner
-from .mocking import FormSpawner
 from .test_api import next_event
-from .utils import api_request
+from .utils import (
-from .utils import async_requests
+    AsyncSession,
-from .utils import AsyncSession
+    api_request,
-from .utils import get_page
+    async_requests,
-from .utils import public_host
+    get_page,
-from .utils import public_url
+    public_host,
+    public_url,
+)
 
 
 async def test_root_no_auth(app):

jupyterhub/tests/test_proxy.py

@@ -3,8 +3,7 @@ import json
 import os
 from contextlib import contextmanager
 from subprocess import Popen
-from urllib.parse import quote
+from urllib.parse import quote, urlparse
-from urllib.parse import urlparse
 
 import pytest
 from traitlets.config import Config
@@ -12,8 +11,7 @@ from traitlets.config import Config
 from ..utils import url_path_join as ujoin
 from ..utils import wait_for_http_server
 from .mocking import MockHub
-from .test_api import add_user
+from .test_api import add_user, api_request
-from .test_api import api_request
 from .utils import skip_if_ssl
 
 

jupyterhub/tests/test_roles.py

@@ -8,14 +8,11 @@ import pytest
 from pytest import mark
 from tornado.log import app_log
 
-from .. import orm
+from .. import orm, roles
-from .. import roles
+from ..scopes import get_scopes_for, scope_definitions
-from ..scopes import get_scopes_for
-from ..scopes import scope_definitions
 from ..utils import utcnow
 from .mocking import MockHub
-from .utils import add_user
+from .utils import add_user, api_request
-from .utils import api_request
 
 
 @mark.role

jupyterhub/tests/test_scopes.py

@@ -7,22 +7,20 @@ from pytest import mark
 from tornado import web
 from tornado.httputil import HTTPServerRequest
 
-from .. import orm
+from .. import orm, roles, scopes
-from .. import roles
-from .. import scopes
 from ..handlers import BaseHandler
-from ..scopes import _check_scope_access
+from ..scopes import (
-from ..scopes import _expand_self_scope
+    Scope,
-from ..scopes import _intersect_expanded_scopes
+    _check_scope_access,
-from ..scopes import expand_scopes
+    _expand_self_scope,
-from ..scopes import get_scopes_for
+    _intersect_expanded_scopes,
-from ..scopes import identify_scopes
+    expand_scopes,
-from ..scopes import needs_scope
+    get_scopes_for,
-from ..scopes import parse_scopes
+    identify_scopes,
-from ..scopes import Scope
+    needs_scope,
-from .utils import add_user
+    parse_scopes,
-from .utils import api_request
+)
-from .utils import auth_header
+from .utils import add_user, api_request, auth_header
 
 
 def get_handler_with_scopes(scopes):

jupyterhub/tests/test_services.py

@@ -8,14 +8,15 @@ from async_generator import asynccontextmanager
 
 from .. import orm
 from ..roles import update_roles
-from ..utils import exponential_backoff
+from ..utils import (
-from ..utils import maybe_future
+    exponential_backoff,
-from ..utils import random_port
+    maybe_future,
-from ..utils import url_path_join
+    random_port,
-from ..utils import wait_for_http_server
+    url_path_join,
+    wait_for_http_server,
+)
 from .mocking import public_url
-from .utils import async_requests
+from .utils import async_requests, skip_if_ssl
-from .utils import skip_if_ssl
 
 mockservice_path = os.path.dirname(os.path.abspath(__file__))
 mockservice_py = os.path.join(mockservice_path, 'mockservice.py')

jupyterhub/tests/test_services_auth.py

@@ -4,9 +4,7 @@ import os
 import sys
 from binascii import hexlify
 from unittest import mock
-from urllib.parse import parse_qs
+from urllib.parse import parse_qs, quote, urlparse
-from urllib.parse import quote
-from urllib.parse import urlparse
 
 import pytest
 from bs4 import BeautifulSoup
@@ -14,14 +12,11 @@ from pytest import raises
 from tornado.httputil import url_concat
 from tornado.log import app_log
 
-from .. import orm
+from .. import orm, roles, scopes
-from .. import roles
-from .. import scopes
 from ..services.auth import _ExpiringDict
 from ..utils import url_path_join
 from .mocking import public_url
-from .utils import async_requests
+from .utils import AsyncSession, async_requests
-from .utils import AsyncSession
 
 # mock for sending monotonic counter way into the future
 monotonic_future = mock.patch('time.monotonic', lambda: sys.maxsize)

jupyterhub/tests/test_singleuser.py

@@ -2,20 +2,18 @@
 import os
 import sys
 from contextlib import contextmanager
-from subprocess import CalledProcessError
+from subprocess import CalledProcessError, check_output
-from subprocess import check_output
 from unittest import mock
 from urllib.parse import urlparse
 
 import pytest
 
 import jupyterhub
+
 from .. import orm
 from ..utils import url_path_join
-from .mocking import public_url
+from .mocking import StubSingleUserSpawner, public_url
-from .mocking import StubSingleUserSpawner
+from .utils import AsyncSession, async_requests
-from .utils import async_requests
-from .utils import AsyncSession
 
 
 @contextmanager

jupyterhub/tests/test_spawner.py

@@ -16,14 +16,10 @@ import pytest
 
 from .. import orm
 from .. import spawner as spawnermod
-from ..objects import Hub
+from ..objects import Hub, Server
-from ..objects import Server
+from ..spawner import LocalProcessSpawner, Spawner
-from ..spawner import LocalProcessSpawner
-from ..spawner import Spawner
 from ..user import User
-from ..utils import AnyTimeoutError
+from ..utils import AnyTimeoutError, new_token, url_path_join
-from ..utils import new_token
-from ..utils import url_path_join
 from .mocking import public_url
 from .test_api import add_user
 from .utils import async_requests

jupyterhub/tests/test_traitlets.py

@@ -1,10 +1,7 @@
 import pytest
-from traitlets import HasTraits
+from traitlets import HasTraits, TraitError
-from traitlets import TraitError
 
-from jupyterhub.traitlets import ByteSpecification
+from jupyterhub.traitlets import ByteSpecification, Command, URLPrefix
-from jupyterhub.traitlets import Command
-from jupyterhub.traitlets import URLPrefix
 
 
 def test_url_prefix():

jupyterhub/tests/test_version.py

@@ -3,8 +3,7 @@ import logging
 
 import pytest
 
-from .._version import _check_version
+from .._version import _check_version, reset_globals
-from .._version import reset_globals
 
 
 def setup_function(function):

jupyterhub/tests/utils.py

@@ -7,11 +7,9 @@ import pytest
 import requests
 from certipy import Certipy
 
-from jupyterhub import metrics
+from jupyterhub import metrics, orm
-from jupyterhub import orm
 from jupyterhub.objects import Server
-from jupyterhub.roles import assign_default_roles
+from jupyterhub.roles import assign_default_roles, update_roles
-from jupyterhub.roles import update_roles
 from jupyterhub.utils import url_path_join as ujoin
 
 

jupyterhub/traitlets.py

@@ -4,13 +4,7 @@ Traitlets that are used in JupyterHub
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 import entrypoints
-from traitlets import Integer
+from traitlets import Integer, List, TraitError, TraitType, Type, Undefined, Unicode
-from traitlets import List
-from traitlets import TraitError
-from traitlets import TraitType
-from traitlets import Type
-from traitlets import Undefined
-from traitlets import Unicode
 
 
 class URLPrefix(Unicode):

jupyterhub/user.py

@@ -3,34 +3,21 @@
 import json
 import warnings
 from collections import defaultdict
-from datetime import datetime
+from datetime import datetime, timedelta
-from datetime import timedelta
+from urllib.parse import quote, urlparse
-from urllib.parse import quote
-from urllib.parse import urlparse
 
 from sqlalchemy import inspect
-from tornado import gen
+from tornado import gen, web
-from tornado import web
 from tornado.httputil import urlencode
 from tornado.log import app_log
 
 from . import orm
-from ._version import __version__
+from ._version import __version__, _check_version
-from ._version import _check_version
+from .crypto import CryptKeeper, EncryptionUnavailable, InvalidToken, decrypt, encrypt
-from .crypto import CryptKeeper
+from .metrics import RUNNING_SERVERS, TOTAL_USERS
-from .crypto import decrypt
-from .crypto import encrypt
-from .crypto import EncryptionUnavailable
-from .crypto import InvalidToken
-from .metrics import RUNNING_SERVERS
-from .metrics import TOTAL_USERS
 from .objects import Server
 from .spawner import LocalProcessSpawner
-from .utils import AnyTimeoutError
+from .utils import AnyTimeoutError, make_ssl_context, maybe_future, url_path_join
-from .utils import make_ssl_context
-from .utils import maybe_future
-from .utils import url_path_join
-
 
 # detailed messages about the most common failure-to-start errors,
 # which manifest timeouts during start

jupyterhub/utils.py

@@ -16,18 +16,14 @@ import threading
 import uuid
 import warnings
 from binascii import b2a_hex
-from datetime import datetime
+from datetime import datetime, timezone
-from datetime import timezone
 from hmac import compare_digest
 from operator import itemgetter
 
 from async_generator import aclosing
 from sqlalchemy.exc import SQLAlchemyError
-from tornado import gen
+from tornado import gen, ioloop, web
-from tornado import ioloop
+from tornado.httpclient import AsyncHTTPClient, HTTPError
-from tornado import web
-from tornado.httpclient import AsyncHTTPClient
-from tornado.httpclient import HTTPError
 from tornado.log import app_log
 
 # For compatibility with python versions 3.6 or earlier.
@@ -477,6 +473,7 @@ def print_stacks(file=sys.stderr):
     # no need to add them to startup
     import asyncio
     import traceback
+
     from .log import coroutine_frames
 
     print("Active threads: %i" % threading.active_count(), file=file)

pyproject.toml

@@ -1,3 +1,6 @@
+[tool.isort]
+profile = "black"
+
 [tool.black]
 skip-string-normalization = true
 target_version = [

setup.py

@@ -9,13 +9,11 @@ import shutil
 import sys
 from subprocess import check_call
 
-from setuptools import Command
+from setuptools import Command, setup
-from setuptools import setup
 from setuptools.command.bdist_egg import bdist_egg
 from setuptools.command.build_py import build_py
 from setuptools.command.sdist import sdist
 
-
 v = sys.version_info
 if v[:2] < (3, 6):
     error = "ERROR: JupyterHub requires Python version 3.6 or above."