code: def test_plotting_with_float_index_works_apply(self):
      # GH 7025
      df = DataFrame(
          {
              "def": [1, 1, 1, 2, 2, 2, 3, 3, 3],
              "val": np.random.default_rng(2).standard_normal(9),
          },
          index=[1.0, 2.0, 3.0, 1.0, 2.0, 3.0, 1.0, 2.0, 3.0],
      )
      df.groupby("def")["val"].apply(lambda x: x.plot())
  
file_path: pandas/pandas/tests/plotting/test_groupby.py
imports: import numpy
  import pytest
  from pandas import DataFrame, Index, Series
  from pandas.tests.plotting.common import _check_axes_shape, _check_legend_labels
label_desc: Use image node_id 5 for calling the TestDataFrameGroupByPlots obj's underlying member method code with example usage: obj.test_plotting_with_float_index_works_apply() without return types