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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 _make_agent(self, entrez_id, text_id):
 """Make an Agent object, appropriately grounded. Parameters entrez_id : str Entrez id number text_id : str A plain text systematic name, or None if not listed. Returns ------- agent : indra.statements.Agent A grounded agent object. """

        hgnc_name, db_refs = self._make_db_refs(entrez_id, text_id)
        if hgnc_name is not None:
            name = hgnc_name
        elif text_id is not None:
            name = text_id
        # Handle case where the name is None
        else:
            return None

        return Agent(name, db_refs=db_refs)