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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 create_index_if_missing(self, index, settings=None):
 """Creates an index if it doesn't already exist. If supplied, settings must be a dictionary. :param index: the name of the index :keyword settings: a settings object or a dict containing settings """

        try:
            return self.create_index(index, settings)
        except IndexAlreadyExistsException as e:
            return e.result