TYP: Fix mypy build errors in core modules

Author: davidjcastrejon

pandas/core/frame.py

@@ -5571,6 +5571,7 @@ def set_axis(
         klass=_shared_doc_kwargs["klass"],
         optional_reindex=_shared_doc_kwargs["optional_reindex"],
     )
+    # error: Cannot determine type of 'reindex'
     def reindex(
         self,
         labels=None,
@@ -6089,6 +6090,7 @@ def _replace_columnwise(
         return res.__finalize__(self)
 
     @doc(NDFrame.shift, klass=_shared_doc_kwargs["klass"])
+    # error: Cannot determine type of 'shift'
     def shift(
         self,
         periods: int | Sequence[int] = 1,

pandas/core/indexes/multi.py

@@ -1436,7 +1436,7 @@ def f(dtype) -> bool:
         return any(f(level.dtype) for level in self.levels)
 
     # Cannot determine type of "memory_usage"
-    @doc(Index.memory_usage)
+    @doc(Index.memory_usage)  # type: ignore[has-type]
     def memory_usage(self, deep: bool = False) -> int:
         # we are overwriting our base class to avoid
         # computing .values here which could materialize