code: def test_boxplot_empty_column(self):
      df = DataFrame(np.random.default_rng(2).standard_normal((20, 4)))
      df.loc[:, 0] = np.nan
      _check_plot_works(df.boxplot, return_type="axes")
  
imports: import itertools
  import string
  import numpy
  import pytest
  from pandas import DataFrame, MultiIndex, Series, date_range, plotting, timedelta_range
  import pandas._testing
  from pandas.tests.plotting.common import _check_axes_shape, _check_box_return_type, _check_plot_works, _check_ticks_props, _check_visible
  from pandas.io.formats.printing import pprint_thing
label_desc: Use image node_id 14 for calling the TestDataFramePlots obj's underlying member method code with example usage: obj.test_boxplot_empty_column() without return types