SELECT Post.id, title, SUBSTR(Post.content, 0, 300), Post.created, Post.user_id, User.username
 FROM Post
 JOIN User ON Post.user_id = User.id;

class User(Base):
    __tablename__ = 'user'
    id = Column(Integer, primary_key=True)
    email = Column(String(250), nullable=False)
    username = Column(String(250), nullable=True)
    firstname = Column(String(250), nullable=True)
    lastname = Column(String(250), nullable=True)
    password = Column(String(250), nullable=False)
    role = Column(String(20), nullable=False)

class Post(Base):
    __tablename__ = 'post'
    id = Column(Integer, primary_key=True)
    title = Column(String(250), nullable=False)
    content = Column(String(250), nullable=False)
    created = Column(Integer, nullable=False)
    user_id = Column(Integer, ForeignKey('user.id'), nullable=False)