def insertDomain(self, domain, indegree=0, outdegree=0):
		'''增加一个域名'''
		cur = self.conn.cursor()
		cur.execute("INSERT INTO Domains VALUES (NULL,?,?,?)", (domain, indegree, outdegree))
		# 写入到文件中
		self.conn.commit()
def queue_when_in_transaction(call):
    if transaction_states[call.using]:
        transaction_states[call.using].push((call, (), {}))
    else:
        return call()