code: def test_slice_dates_inexact(df_dates):
      """Test output of slice on date column."""
      actual = df_dates.select_columns(slice("2011-01", "2011-03"))
      expected = df_dates.loc[:, "2011-01":"2011-03"]
      assert_frame_equal(actual, expected)
  
imports: import datetime
  import re
  from itertools import product
  import numpy
  import pandas
  import pytest
  from pandas.api.types import is_numeric_dtype
  from pandas.testing import assert_frame_equal
  from janitor.functions.utils import DropLabel, get_columns, patterns
label_desc: Use image node_id 26 for calling a global function with example usage: test_slice_dates_inexact(df_dates) without return types