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 mkhead(repo: 'Repo', path: PathLike) -> 'Head':
    """:return: New branch/head instance"""
    return git.Head(repo, git.Head.to_full_path(path))