[mypy] solve some mypy issues

Change-Id: Ie014bdfa237974e2cb3f7ee39fa730292f79823d
---
M pywikibot/__init__.py
M pywikibot/backports.py
2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/pywikibot/__init__.py b/pywikibot/__init__.py
index 3e14eb0..454c4bf 100644
--- a/pywikibot/__init__.py
+++ b/pywikibot/__init__.py
@@ -12,7 +12,7 @@
 from contextlib import suppress
 from queue import Queue
 from time import sleep as time_sleep
-from typing import Any, Optional, Union
+from typing import Any, Optional, Union, cast
 from urllib.parse import urlparse
 from warnings import warn
 
@@ -224,6 +224,7 @@
     if not isinstance(fam, Family):
         fam = Family.load(fam)
 
+    fam = cast(Family, fam)
     interface = interface or fam.interface(code)
 
     # config.usernames is initialised with a defaultdict for each family name
@@ -237,6 +238,7 @@
 
     if not isinstance(interface, type):
         # If it isn't a class, assume it is a string
+        interface = cast(str, interface)
         try:
             tmp = __import__('pywikibot.site', fromlist=[interface])
         except ImportError:
diff --git a/pywikibot/backports.py b/pywikibot/backports.py
index c1a7d05..f2a77ec 100644
--- a/pywikibot/backports.py
+++ b/pywikibot/backports.py
@@ -40,14 +40,14 @@
         def __exit__(self, *excinfo: Any) -> None:
             pass
 else:
-    from contextlib import nullcontext  # type: ignore[misc]
+    from contextlib import nullcontext  # type: ignore[assignment]
 
 
 # queue
 if PYTHON_VERSION < (3, 7):
     from queue import Queue as SimpleQueue
 else:
-    from queue import SimpleQueue  # type: ignore[misc]
+    from queue import SimpleQueue  # type: ignore[assignment]
 
 
 # typing
@@ -143,8 +143,8 @@
             return string[:-len(suffix)]
         return string
 else:
-    removeprefix = str.removeprefix  # type: ignore[attr-defined]
-    removesuffix = str.removesuffix  # type: ignore[attr-defined]
+    removeprefix = str.removeprefix  # type: ignore[assignment]
+    removesuffix = str.removesuffix  # type: ignore[assignment]
 
 
 # bpo-38200
@@ -163,7 +163,7 @@
         next(b, None)
         return zip(a, b)
 else:
-    from itertools import pairwise
+    from itertools import pairwise  # type: ignore[no-redef]
 
 
 # gh-98363
@@ -203,4 +203,4 @@
         if group:
             yield tuple(group)
 else:
-    from itertools import batched
+    from itertools import batched  # type: ignore[no-redef]

