code: def test_unit_parser(self, unit, np_unit, wrapper):
      # validate all units, GH 6855, GH 21762
      # array-likes
      expected = TimedeltaIndex(
          [np.timedelta64(i, np_unit) for i in np.arange(5).tolist()],
          dtype="m8[ns]",
      )
      # TODO(2.0): the desired output dtype may have non-nano resolution
      msg = f"'{unit}' is deprecated and will be removed in a future version."
  
      if (unit, np_unit) in (
          ("u", "us"),
          ("U", "us"),
          ("n", "ns"),
          ("N", "ns"),
      ):
          warn = FutureWarning
      else:
          warn = FutureWarning
          msg = "The 'unit' keyword in TimedeltaIndex construction is deprecated"
      with tm.assert_produces_warning(warn, match=msg):
          result = to_timedelta(wrapper(range(5)), unit=unit)
          tm.assert_index_equal(result, expected)
          result = TimedeltaIndex(wrapper(range(5)), unit=unit)
          tm.assert_index_equal(result, expected)
  
          str_repr = [f"{x}{unit}" for x in np.arange(5)]
          result = to_timedelta(wrapper(str_repr))
          tm.assert_index_equal(result, expected)
          result = to_timedelta(wrapper(str_repr))
          tm.assert_index_equal(result, expected)
  
          # scalar
          expected = Timedelta(
              np.timedelta64(2, np_unit).astype("timedelta64[ns]")
          )
          result = to_timedelta(2, unit=unit)
          assert result == expected
          result = Timedelta(2, unit=unit)
          assert result == expected
  
          result = to_timedelta(f"2{unit}")
          assert result == expected
          result = Timedelta(f"2{unit}")
          assert result == expected
  
imports: from datetime import timedelta
  from itertools import product
  import numpy
  import pytest
  from pandas._libs.tslibs import OutOfBoundsTimedelta
  from pandas._libs.tslibs.dtypes import NpyDatetimeUnit
  from pandas import Index, NaT, Timedelta, TimedeltaIndex, offsets, to_timedelta
  import pandas._testing
label_desc: Use image node_id 3 for calling the TestTimedeltaConstructorUnitKeyword obj's underlying member method code with example usage: obj.test_unit_parser(unit, np_unit, wrapper) without return types