code: def normalize_timestamp_column(ts, fallback_dtype="datetime64[ms]"):
      """
      Normalize the input timestamp column to one of the cuDF timestamp dtypes.
  
      If the input column's dtype isn't an np.datetime64, cast the column to the
      supplied `fallback_dtype` parameter.
  
      Parameters
      ----------
      {params}
  
      Returns
      -------
      column : the input column
      """
      return (
          ts
          if is_datetime_dtype(ts.dtype)
          else ts.astype(fallback_dtype)
      )
  
file_path: cuspatial/python/cuspatial/cuspatial/utils/column_utils.py
imports: from typing import TypeVar
  import numpy
  from cudf.api.types import is_datetime_dtype
  from cudf.core.column.column import column_empty
  from cuspatial.core._column.geometa import Feature_Enum
  from cuspatial.core.dtypes import linestring_dtype, multipoint_dtype, point_dtype, polygon_dtype
label_desc: Use image node_id 2 for calling a global function with example usage: normalize_timestamp_column(ts, fallback_dtype) and returns: unknown