code: def test_where_inplace_no_other():
      # GH#51685
      df = DataFrame({"a": [1.0, 2.0], "b": ["x", "y"]})
      cond = DataFrame({"a": [True, False], "b": [False, True]})
      df.where(cond, inplace=True)
      expected = DataFrame({"a": [1, np.nan], "b": [np.nan, "y"]})
      tm.assert_frame_equal(df, 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 18 for calling a global function with example usage: test_where_inplace_no_other() without return types