Allow __all__ to be typed

Closes gh-1018

Author: sigmavirus24

pycodestyle.py

@@ -169,7 +169,7 @@ def lru_cache(maxsize=128):  # noqa as it's a fake implementation.
         'while',
     )))
 )
-DUNDER_REGEX = re.compile(r'^__([^\s]+)__ = ')
+DUNDER_REGEX = re.compile(r"^__([^\s]+)__(?::\s*[a-zA-Z.0-9_\[\]\"]+)? = ")
 MATCH_CASE_REGEX = re.compile(r'^\s*\b(?:match|case)(\s*)(?=.*\:)')
 BLANK_EXCEPT_REGEX = re.compile(r"except\s*:")
 

testsuite/python38.py

@@ -28,3 +28,17 @@ def f3(
 #: E225:1:18
 if False or (x :=1):
     pass
+#: Okay
+import typing as t
+
+__all__: t.List[str] = []
+
+import logging
+
+logging.getLogger(__name__)
+#: E402
+import typing as t
+
+all_the_things: t.List[str] = []
+
+import logging