old_contents: from zou.app import db
  from zou.app.models.serializer import SerializerMixin
  from zou.app.models.base import BaseMixin
  
  
  class Department(db.Model, BaseMixin, SerializerMixin):
      """
      Studio department like modeling, animation, etc.
      """
  
      name = db.Column(db.String(80), unique=True, nullable=False)
      color = db.Column(db.String(7), nullable=False)
      shotgun_id = db.Column(db.Integer, index=True)
  
new_contents: from zou.app import db
  from zou.app.models.serializer import SerializerMixin
  from zou.app.models.base import BaseMixin
  
  
  class Department(db.Model, BaseMixin, SerializerMixin):
      """
      Studio department like modeling, animation, etc.
      """
  
      name = db.Column(db.String(80), unique=True, nullable=False)
      color = db.Column(db.String(7), nullable=False)
  
subject: remove wrong column addition