Deletes all requests and responses for a given flow from the database.

def DeleteAllFlowRequestsAndResponses(self, client_id, flow_id, cursor=None):
    """Deletes all requests and responses for a given flow from the database."""
    args = [db_utils.ClientIDToInt(client_id), db_utils.FlowIDToInt(flow_id)]
    res_query = "DELETE FROM flow_responses WHERE client_id=%s AND flow_id=%s"
    cursor.execute(res_query, args)
    req_query = "DELETE FROM flow_requests WHERE client_id=%s AND flow_id=%s"
    cursor.execute(req_query, args)