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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 register_outgoing_conn(self, conn):
 """Add outgoing connection into the heap."""

        assert conn, "conn is required"
        conn.set_outbound_pending_change_callback(self._on_conn_change)
        self.connections.append(conn)
        self._set_on_close_cb(conn)
        self._on_conn_change()