code: def test_constructor_freq_mult_dti_compat_month(self, mult):
      pidx = period_range(
          start="2014-04-01", freq=f"{mult}M", periods=10
      )
      expected = date_range(
          start="2014-04-01", freq=f"{mult}ME", periods=10
      ).to_period(f"{mult}M")
      tm.assert_index_equal(pidx, expected)
  
imports: import numpy
  import pytest
  from pandas._libs.tslibs.period import IncompatibleFrequency
  from pandas.core.dtypes.dtypes import PeriodDtype
  from pandas import Index, NaT, Period, PeriodIndex, Series, date_range, offsets, period_range
  import pandas._testing
  from pandas.core.arrays import PeriodArray
label_desc: Use image node_id 25 for calling the TestPeriodIndex obj's underlying member method code with example usage: obj.test_constructor_freq_mult_dti_compat_month(mult) without return types