PB-911 Add stubs for environ and gunicorn

Author: schtibe

app/stubs/environ/__init__.pyi

@@ -0,0 +1,36 @@
+# basic implementation of the types of django-environ
+# since this package is neither critical nor widely used and rather of simple
+# nature, API wise, it intentionally contains the minimum needed to satisfy
+# the type checker
+import builtins
+from typing import Dict, List
+from _typeshed import Incomplete  # pylint: disable=import-error
+
+
+class Env:
+
+    def __init__(self) -> None:
+        ...
+
+    def __call__(
+        self, var: builtins.str, cast=..., default=..., parse_default: builtins.bool = False
+    ):
+        ...
+
+    def str(self, var: builtins.str, default=..., multiline: builtins.bool = ...) -> builtins.str:
+        ...
+
+    def bool(self, var: builtins.str, default=...) -> builtins.bool:
+        ...
+
+    def int(self, var: builtins.str, default=...) -> builtins.str:
+        ...
+
+    def list(self,
+             var,
+             cast: Incomplete | None = None,
+             default=...) -> List[builtins.str | builtins.int]:
+        ...
+
+    def dict(self, var, cast=..., default=...) -> Dict[builtins.str, builtins.str | builtins.int]:
+        ...

app/stubs/gunicorn/app/base.pyi

@@ -0,0 +1,7 @@
+# Basic implementation of the type for gunicorn used in wsgi.py
+# Since this is the only place used and very likely not subject to change,
+# this stubbing is intentionally very minimal to just satisfy the type checking
+class BaseApplication:
+
+    def run(self):
+        ...