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 __init__(self, config_d, path=None, resolver=None):
        super().__init__(path=path, resolver=resolver)
        self._collection = {}
        for key, value in config_d.items():
            self._collection[key] = self._from_python(key, value)