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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 marker_index_document_id(self):
 """ Generate an id for the indicator document. """

        params = '%s:%s:%s' % (self.index, self.doc_type, self.update_id)
        return hashlib.sha1(params.encode('utf-8')).hexdigest()