diff --git a/base-notebook/jupyter_notebook_config.py b/base-notebook/jupyter_notebook_config.py
index e0c7d12a..ad41dafa 100644
--- a/base-notebook/jupyter_notebook_config.py
+++ b/base-notebook/jupyter_notebook_config.py
@@ -45,18 +45,13 @@ distinguished_name = req_distinguished_name
             "openssl",
             "req",
             "-new",
-            "-newkey",
-            "rsa:2048",
-            "-days",
-            "365",
+            "-newkey=rsa:2048",
+            "-days=365",
             "-nodes",
             "-x509",
-            "-subj",
-            "/C=XX/ST=XX/L=XX/O=generated/CN=generated",
-            "-keyout",
-            pem_file,
-            "-out",
-            pem_file,
+            "-subj=/C=XX/ST=XX/L=XX/O=generated/CN=generated",
+            f"-keyout={pem_file}",
+            f"-out={pem_file}",
         ]
     )
     # Restrict access to the file
diff --git a/conftest.py b/conftest.py
index d13654bf..4c3056ad 100644
--- a/conftest.py
+++ b/conftest.py
@@ -97,7 +97,10 @@ def container(docker_client, image_name):
     Yields the container instance and kills it when the caller is done with it.
     """
     container = TrackedContainer(
-        docker_client, image_name, detach=True, ports={"8888/tcp": 8888}
+        docker_client,
+        image_name,
+        detach=True,
+        ports={"8888/tcp": 8888},
     )
     yield container
     container.remove()
diff --git a/scipy-notebook/test/data/matplotlib_1.py b/scipy-notebook/test/data/matplotlib_1.py
index aab63ea7..57a93e70 100644
--- a/scipy-notebook/test/data/matplotlib_1.py
+++ b/scipy-notebook/test/data/matplotlib_1.py
@@ -15,7 +15,9 @@ fig, ax = plt.subplots()
 ax.plot(t, s)
 
 ax.set(
-    xlabel="time (s)", ylabel="voltage (mV)", title="About as simple as it gets, folks"
+    xlabel="time (s)",
+    ylabel="voltage (mV)",
+    title="About as simple as it gets, folks",
 )
 ax.grid()
 # Note that the test can be run headless by checking if an image is produced
diff --git a/tagging/create_manifests.py b/tagging/create_manifests.py
index 03f984aa..b4064d82 100755
--- a/tagging/create_manifests.py
+++ b/tagging/create_manifests.py
@@ -20,7 +20,10 @@ MARKDOWN_LINE_BREAK = "<br />"
 
 
 def append_build_history_line(
-    short_image_name: str, owner: str, wiki_path: str, all_tags: List[str]
+    short_image_name: str,
+    owner: str,
+    wiki_path: str,
+    all_tags: List[str],
 ) -> None:
     logger.info("Appending build history line")
 
diff --git a/tagging/taggers.py b/tagging/taggers.py
index 392b2179..2f95d09b 100644
--- a/tagging/taggers.py
+++ b/tagging/taggers.py
@@ -25,7 +25,9 @@ def _get_env_variable(container, variable: str) -> str:
 def _get_pip_package_version(container, package: str) -> str:
     VERSION_PREFIX = "Version: "
     package_info = DockerRunner.run_simple_command(
-        container, cmd=f"pip show {package}", print_result=False
+        container,
+        cmd=f"pip show {package}",
+        print_result=False,
     )
     version_line = package_info.split("\n")[1]
     assert version_line.startswith(VERSION_PREFIX)
diff --git a/test/helpers.py b/test/helpers.py
index b48ef70a..a36cab06 100644
--- a/test/helpers.py
+++ b/test/helpers.py
@@ -143,13 +143,15 @@ class CondaPackageHelper:
                     continue
                 current = min(inst_vs, key=CondaPackageHelper.semantic_cmp)
                 newest = avail_vs[-1]
-                if avail_vs and current != newest:
-                    if CondaPackageHelper.semantic_cmp(
-                        current
-                    ) < CondaPackageHelper.semantic_cmp(newest):
-                        self.comparison.append(
-                            {"Package": pkg, "Current": current, "Newest": newest}
-                        )
+                if (
+                    avail_vs
+                    and current != newest
+                    and CondaPackageHelper.semantic_cmp(current)
+                    < CondaPackageHelper.semantic_cmp(newest)
+                ):
+                    self.comparison.append(
+                        {"Package": pkg, "Current": current, "Newest": newest}
+                    )
         return self.comparison
 
     @staticmethod