Add missing List imports.

stdlib/2/calendar.pyi

@@ -1,4 +1,4 @@
-from typing import Any, Iterable, Optional, Tuple, Sequence
+from typing import Any, Iterable, List, Optional, Tuple, Sequence
 import datetime
 
 LocaleType = Tuple[Optional[str], Optional[str]]

stdlib/2/urllib2.pyi

@@ -1,5 +1,5 @@
 
-from typing import AnyStr, Dict, Union
+from typing import AnyStr, Dict, List, Union
 from urllib import addinfourl
 
 class URLError(IOError):