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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 _check_and_assign_normalization_members(self, normalization_ctor, normalization_kwargs):
 """Checks that the normalization constructor is callable."""

    if isinstance(normalization_ctor, six.string_types):
      normalization_ctor = util.parse_string_to_constructor(normalization_ctor)
    if normalization_ctor is not None and not callable(normalization_ctor):
      raise ValueError(
          "normalization_ctor must be a callable or a string that specifies "
          "a callable, got {}.".format(normalization_ctor))
    self._normalization_ctor = normalization_ctor
    self._normalization_kwargs = normalization_kwargs