nothing

class Post(db.Model):
    """
    This is a class represents a model-object for a post entity.
        - id (integer): This is a primary key, self creating index by simply counter.
        - title (string): title
        - html (string): content
        - time (datetime): timestamp at creating
        - user_mail (string): this is foreign key that connects with user entity, ondelete param set as RESTRICT for
            restrict deleting, which mean while trying delete a user object, sqlalchemy do not try to delete all
            connected posts with one
    """
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(120))
    html = db.Column(db.String(10**6))
    time = db.Column(db.DateTime, default=datetime.now)
    user_mail = db.Column(db.String(36), db.ForeignKey("user.mail", ondelete="RESTRICT"))

    @property
    def cut(self):
        return self.html[0:min(400, len(self.html))]

    @staticmethod
    def add(**kwargs):
        db.session.add(Post(**kwargs))


# take a quest about sqlite politics (restrict, cascade)
class User(db.Model):
    """
    This is a class represents a model-object for user entity.
    @type mail: string
    @param mail: This is a primary key, that mean registred user's e-mail.
    @type abut: string
    @param abut: Something about user, that he had wrote at registration.
    @type regd: datetime
    @param regd: Date & time of registration.
    @type brth: datetime
    @param brth: Birthsday.
    @type auth: bool
    @param auth: Is user authenticated.
    @type grup: string
    @param grup: Just a string for group classification. Simply. Hard. Works.
    @type posts: relationship
    @param posts: backref for connecting users with posts.
    """

    admin = None

    mail = db.Column(db.String(36), primary_key=True)
    abut = db.Column(db.String(10**6))
    regd = db.Column(db.DateTime, default=datetime.now)
    brth = db.Column(db.DateTime)
    pswd = db.Column(db.String(36))
    auth = db.Column(db.Boolean)
    grup = db.Column(db.String(16))
    posts = db.relationship("Post", backref="user", lazy="dynamic")