code: def test_conversion(self, pc, axis):
      rs = pc.convert(["2012-1-1"], None, axis)[0]
      xp = Period("2012-1-1").ordinal
      assert rs == xp
  
      rs = pc.convert("2012-1-1", None, axis)
      assert rs == xp
  
      rs = pc.convert([date(2012, 1, 1)], None, axis)[0]
      assert rs == xp
  
      rs = pc.convert(date(2012, 1, 1), None, axis)
      assert rs == xp
  
      rs = pc.convert([Timestamp("2012-1-1")], None, axis)[0]
      assert rs == xp
  
      rs = pc.convert(Timestamp("2012-1-1"), None, axis)
      assert rs == xp
  
      rs = pc.convert("2012-01-01", None, axis)
      assert rs == xp
  
      rs = pc.convert("2012-01-01 00:00:00+0000", None, axis)
      assert rs == xp
  
      rs = pc.convert(
          np.array(
              ["2012-01-01 00:00:00", "2012-01-02 00:00:00"],
              dtype="datetime64[ns]",
          ),
          None,
          axis,
      )
      assert rs[0] == xp
  
imports: from datetime import date, datetime
  import subprocess
  import sys
  import numpy
  import pytest
  import pandas._config.config
  from pandas._libs.tslibs import to_offset
  from pandas import Index, Period, PeriodIndex, Series, Timestamp, arrays, date_range
  import pandas._testing
  from pandas.plotting import deregister_matplotlib_converters, register_matplotlib_converters
  from pandas.tseries.offsets import Day, Micro, Milli, Second
label_desc: Use image node_id 4 for calling the TestPeriodConverter obj's underlying member method code with example usage: obj.test_conversion(pc, axis) without return types