text: from sqlalchemy import Column, Integer
  
  from changes.config import db
  from changes.db.types.guid import GUID
  
  
  class ItemSequence(db.Model):
      __tablename__ = 'itemsequence'
  
      parent_id = Column(GUID, nullable=False, primary_key=True)
      value = Column(Integer, default=0, server_default='0', nullable=False,
                     primary_key=True)
  