def _get_user_(self, username=None, emial=None, id=None):
        if username:
            dbUser = User.query.filter_by(username=username).first()
            if dbUser:
                self.email = dbUser.email
                self.username = dbUser.username
                self.passwd = dbUser.passwd
                self.id = dbUser.id

                return self

        elif emial:
            dbUser = User.query.filter_by(username=username).first()
            if dbUser:
                self.email = dbUser.email
                self.username = dbUser.username
                self.passwd = dbUser.passwd
                self.id = dbUser.id

                return self

            return self

        elif id:
            dbUser = User.query.filter_by(username=username).first()
            if dbUser:
                self.email = dbUser.email
                self.username = dbUser.username
                self.passwd = dbUser.passwd
                self.id = dbUser.id

                return self

            return self
        else:
            return None

如上所示，如何把代码压缩成一个dict