code: def check_collision( self, history_id_key, history_id, block_id, checked_ops, affected_opcodes ):
          
  
          return BlockstackDB.check_collision_state( self.collisions, history_id_key, history_id, block_id, checked_ops, affected_opcodes )
docs: Given a history ID, see if it already exists
          at the given block ID (i.e. it's not expired).
          Return True if so; False if not.
          If there is a collision, set the __collided__ field in each checked_ops that
          has a matching history_id value and has an opcode in affected_opcodes.