code: def _validate_td64_dtype(dtype) -> DtypeObj:
      dtype = pandas_dtype(dtype)
      if is_dtype_equal(dtype, np.dtype("timedelta64")):
          # no precision disallowed GH#24806
          msg = (
              "Passing in 'timedelta' dtype with no precision is not allowed. "
              "Please pass in 'timedelta64[ns]' instead."
          )
          raise ValueError(msg)
  
      if (
          not isinstance(dtype, np.dtype)
          or dtype.kind != "m"
          or not is_supported_unit(get_unit_from_dtype(dtype))
      ):
          raise ValueError(
              f"dtype {dtype} cannot be converted to timedelta64[ns]"
          )
  
      return dtype
  
imports: from __future__ import annotations
  from datetime import timedelta
  import operator
  from typing import TYPE_CHECKING, Iterator, cast
  import warnings
  import numpy
  from pandas._libs import lib, tslibs
  from pandas._libs.tslibs import BaseOffset, NaT, NaTType, Tick, Timedelta, astype_overflowsafe, get_supported_reso, get_unit_from_dtype, iNaT, is_supported_unit, npy_unit_to_abbrev, periods_per_second, to_offset
  from pandas._libs.tslibs.conversion import precision_from_unit
  from pandas._libs.tslibs.fields import get_timedelta_days, get_timedelta_field
  from pandas._libs.tslibs.timedeltas import array_to_timedelta64, floordiv_object_array, ints_to_pytimedelta, parse_timedelta_unit, truediv_object_array
  from pandas._typing import AxisInt, DateTimeErrorChoices, DtypeObj, NpDtype, npt
  from pandas.compat.numpy import function
  from pandas.util._validators import validate_endpoints
  from pandas.core.dtypes.common import TD64NS_DTYPE, is_dtype_equal, is_extension_array_dtype, is_float_dtype, is_integer_dtype, is_object_dtype, is_scalar, is_string_dtype, is_timedelta64_dtype, pandas_dtype
  from pandas.core.dtypes.missing import isna
  from pandas.core import nanops
  from pandas.core.array_algos import datetimelike_accumulations
  from pandas.core.arrays import datetimelike
  from pandas.core.arrays._ranges import generate_regular_range
  import pandas.core.common
  from pandas.core.ops import roperator
  from pandas.core.ops.common import unpack_zerodim_and_defer
label_desc: Use image node_id 5 for calling a global function with example usage: _validate_td64_dtype(dtype) and returns: dtype