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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 list_contributors(self, project_id=None, language_code=None):
 """ Returns the list of contributors """

        data = self._run(
            url_path="contributors/list",
            id=project_id,
            language=language_code
        )
        return data['result'].get('contributors', [])