BUG: Fix Index.get_level_values() mishandling of boolean, pd.NA, np.nan, and pd.NaT levels

pandas/_libs/__init__.py

@@ -1,4 +1,5 @@
 __all__ = [
+    "NA",
     "Interval",
     "NaT",
     "NaTType",
@@ -16,6 +17,7 @@
 import pandas._libs.pandas_parser  # isort: skip # type: ignore[reportUnusedImport]
 import pandas._libs.pandas_datetime  # noqa: F401 # isort: skip # type: ignore[reportUnusedImport]
 from pandas._libs.interval import Interval
+from pandas._libs.missing import NA
 from pandas._libs.tslibs import (
     NaT,
     NaTType,

pandas/core/indexes/base.py

@@ -2084,7 +2084,10 @@ def _validate_index_level(self, level) -> None:
         verification must be done like in MultiIndex.
 
         """
-        if isinstance(level, int):
+        if type(level) is int:
+            if isinstance(self.name, int) and level == self.name:
+                return
+
             if level < 0 and level != -1:
                 raise IndexError(
                     "Too many levels: Index has only 1 level, "
@@ -2094,7 +2097,10 @@ def _validate_index_level(self, level) -> None:
                 raise IndexError(
                     f"Too many levels: Index has only 1 level, not {level + 1}"
                 )
-        elif level != self.name:
+
+        elif (
+            isinstance(level, str) and isinstance(self.name, str) and level != self.name
+        ):
             raise KeyError(
                 f"Requested level ({level}) does not match index name ({self.name})"
             )