general: fix some issues after mypy update

my/core/query_range.py

@@ -155,6 +155,7 @@ def _parse_range(
         return parsed_range
 
     err_msg = error_message or RangeTuple.__doc__
+    assert err_msg is not None  # make mypy happy
     after, before, within = None, None, None
 
     none_count = more_itertools.ilen(filter(lambda o: o is None, list(unparsed_range)))

my/instagram/common.py

@@ -68,6 +68,6 @@ def _merge_messages(*sources: Iterator[Res[Message]]) -> Iterator[Res[Message]]:
             if user is not None:
                 repls['user'] = user
             if len(repls) > 0:
-                m = replace(m, **repls)  # type: ignore[type-var]  # ugh mypy is confused because of Protocol?
+                m = replace(m, **repls)  # type: ignore[type-var, misc]  # ugh mypy is confused because of Protocol?
             mmap[k] = m
             yield m