changed cat_array assignment to cat_array_list

Author: nickleus27

pandas/core/dtypes/dtypes.py

@@ -465,9 +465,11 @@ def _hash_categories(self) -> int:
                 [cat_array, np.arange(len(cat_array), dtype=cat_array.dtype)]
             )
         else:
-            # error: Incompatible types in assignment (expression has type
-            # "List[ndarray]", variable has type "ndarray")
-            cat_array = [cat_array]  # type: ignore[assignment]
+            cat_array_list = [cat_array]
+            combined_hashed = combine_hash_arrays(
+                iter(cat_array_list), num_items=len(cat_array_list)
+            )
+            return np.bitwise_xor.reduce(combined_hashed)
         combined_hashed = combine_hash_arrays(iter(cat_array), num_items=len(cat_array))
         return np.bitwise_xor.reduce(combined_hashed)