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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _GetTimeValue(self, name):
 """Retrieves a date and time value. Args: name (str):
 name of the date and time value, for example "atime" or "mtime". Returns: dfdatetime.DateTimeValues: date and time value or None if not available. """

    timestamp = getattr(self._tsk_file.info.meta, name, None)

    if self._file_system_type in self._TSK_HAS_NANO_FS_TYPES:
      name_fragment = '{0:s}_nano'.format(name)
      fraction_of_second = getattr(
          self._tsk_file.info.meta, name_fragment, None)
    else:
      fraction_of_second = None

    return TSKTime(timestamp=timestamp, fraction_of_second=fraction_of_second)