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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_description(self, description_type='Abstract'):
 """Get DataCite description."""

        if 'descriptions' in self.xml:
            if isinstance(self.xml['descriptions']['description'], list):
                for description in self.xml['descriptions']['description']:
                    if description_type in description:
                        return description[description_type]
            elif isinstance(self.xml['descriptions']['description'], dict):
                description = self.xml['descriptions']['description']
                if description_type in description:
                    return description[description_type]
                elif len(description) == 1:
                    # return the only description
                    return description.values()[0]

        return None