def register_user(self, name, email, login, password):
        if self.user_exist(login):
            return [False, "user with this login already exists"]
        elif self.email_exist(email):
            return [False, "user with this email already exists"]
        try:
            self.first_name, self.surname = name.split()
        except ValueError:
            self.first_name = name
        self.login = login
        self.email = email
        self.password = hashlib.sha256(password.encode()).hexdigest()
        db.session.add(self)
        db.session.commit()
        return [True]


    def change_user_email(self, email):
        if self.email_exist(email):
            return [False, "user with this email already exists"]
        self.email = email