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 _deDuplicate(results):
        found = dict()
        deDuped = list()
        for entry in results:
            dn = entry.get("dn")
            if not dn in found:
                found[dn] = 1
                deDuped.append(entry)

        return deDuped