<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_edge_by_hash(self, edge_hash: str) -> Optional[Edge]: """Look up an edge by the hash of a PyBEL edge data dictionary."""

        return self.session.query(Edge).filter(Edge.sha512 == edge_hash).one_or_none()