code: def test_append_names_dont_match():
      # GH#48288
      midx = MultiIndex.from_arrays([[1, 2], [3, 4]], names=["a", "b"])
      midx2 = MultiIndex.from_arrays([[3], [5]], names=["x", "y"])
      result = midx.append(midx2)
      expected = MultiIndex.from_arrays(
          [[1, 2, 3], [3, 4, 5]], names=None
      )
      tm.assert_index_equal(result, expected)
  
file_path: pandas/pandas/tests/indexes/multi/test_reshape.py
imports: from datetime import datetime
  import numpy
  import pytest
  import pytz
  import pandas
  from pandas import Index, MultiIndex
  import pandas._testing
label_desc: Use image node_id 6 for calling a global function with example usage: test_append_names_dont_match() without return types