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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 make_name(estimator):

 """Helper function that returns the name of estimator or the given string
 if a string is given
 """

  if estimator is not None:
    if isinstance(estimator, six.string_types):
      estimator_name = estimator
    else:
      estimator_name = estimator.__class__.__name__
  else:
    estimator_name = None
  return estimator_name