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 test_ccode_boolean():
    assert ccode(x & y) == "x && y"
    assert ccode(x | y) == "x || y"
    assert ccode(~x) == "!x"
    assert ccode(x & y & z) == "x && y && z"
    assert ccode(x | y | z) == "x || y || z"
    assert ccode((x & y) | z) == "z || x && y"
    assert ccode((x | y) & z) == "z && (x || y)"