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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 get_creators(self, attribute='creatorName'):
 """Get DataCite creators."""

        if 'creators' in self.xml:
            if isinstance(self.xml['creators']['creator'], list):
                return [c[attribute] for c in self.xml['creators']['creator']]
            else:
                return self.xml['creators']['creator'][attribute]

        return None