from app import db

class Content(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    file_name = db.Column(db.String(120), nullable=False)
    duration = db.Column(db.Integer, nullable=False)
    player_id = db.Column(db.Integer, db.ForeignKey('player.id'), nullable=True)
    group_id = db.Column(db.Integer, db.ForeignKey('group.id'), nullable=True)

# other models...