import typing.DefaultDict for annotation fails for Python 3.5.0 and 3.5.1. This generic class was introduced with Python 3.5.2: https://docs.python.org/3/library/typing.html?highlight=typing%20defaultdict#typing.DefaultDict
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ERROR: deletionbot_tests (unittest.loader._FailedTest)
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ImportError: Failed to import test module: deletionbot_tests
Traceback (most recent call last):
File "c:\python350-x64\lib\unittest\loader.py", line 153, in loadTestsFromName
module = __import__(module_name)
File "C:\projects\pywikibot-g4xqx\tests\deletionbot_tests.py", line 13, in <module>
from scripts import delete
File "C:\projects\pywikibot-g4xqx\scripts\delete.py", line 61, in <module>
from typing import DefaultDict, Set
ImportError: cannot import name 'DefaultDict'
======================================================================See https://ci.appveyor.com/project/Ladsgroup/pywikibot-g4xqx/builds/34055924/job/9s5el2co7v37y36y