including custom field in schema with nested Schema

[saksham219]

I have a model with data of some facebook posts:

class Post(db.Model): id = db.Column(db.Integer, primary_key = True) post_id = db.Column(db.String(40), unique = True) post_type = db.Column(db.String(10)) post_created_time = db.Column(db.String(30)) post_content = db.Column(db.Text) post_link = db.Column(db.String(700)) post_likes = db.Column(db.Integer) post_comments = db.Column(db.Integer) post_shares = db.Column(db.Integer) post_photos = db.Column(db.ARRAY(db.String(500))) date_saved = db.Column(db.DateTime, default= datetime.utcnow()) date_updated = db.Column(db.DateTime) page_name = db.Column(db.String(20))