code: def test_where_dataframe_col_match(self):
      df = DataFrame([[1, 2, 3], [4, 5, 6]])
      cond = DataFrame([[True, False, True], [False, False, True]])
  
      result = df.where(cond)
      expected = DataFrame([[1.0, np.nan, 3], [np.nan, np.nan, 6]])
      tm.assert_frame_equal(result, expected)
  
      # this *does* align, though has no matching columns
      cond.columns = ["a", "b", "c"]
      result = df.where(cond)
      expected = DataFrame(np.nan, index=df.index, columns=df.columns)
      tm.assert_frame_equal(result, expected)
  
imports: from datetime import datetime
  from hypothesis import given
  import numpy
  import pytest
  from pandas.core.dtypes.common import is_scalar
  import pandas
  from pandas import DataFrame, DatetimeIndex, Index, Series, StringDtype, Timestamp, date_range, isna
  import pandas._testing
  from pandas._testing._hypothesis import OPTIONAL_ONE_OF_ALL
label_desc: Use image node_id 10 for calling the TestDataFrameIndexingWhere obj's underlying member method code with example usage: obj.test_where_dataframe_col_match() without return types