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 _handle_sigint_if_enabled(self, signum, _frame):
        with self._ignore_sigint_lock:
            self._check_sigint_gate_is_correct()
            threads_ignoring_sigint = self._threads_ignoring_sigint
            ignoring_sigint_v2_engine = self._ignoring_sigint_v2_engine
        if threads_ignoring_sigint == 0 and not ignoring_sigint_v2_engine:
            self.handle_sigint(signum, _frame)