bd

class Client(Base):
    __tablename__ = 'Clients'
    client_id = Column(Integer, primary_key=True, autoincrement=True)
    account_name = Column(String(25), unique=True)
    password = Column(String(25))
    username = Column(String(25))

    def __repr__(self):
        return '<Client: ID {} {}, -- [{}, {}]>'.format(self.client_id, self.account_name, self.password, self.username)


class Contact(Base):
    __tablename__ = 'Contacts'
    owner_id = Column(Integer, ForeignKey('Clients.client_id'), primary_key=True)
    contact_id = Column(Integer, ForeignKey('Clients.client_id'), primary_key=True)

    owner = relationship(Client, foreign_keys=[owner_id])
    contact = relationship(Client, foreign_keys=[contact_id])