How to format SQLAlchemy ORM Postgresql CIDR contains (>>) query

I have a model defined with

from app import db
from sqlalchemy.dialects import postgresql

class TableIpAddress(db.Model):
  __tablename__ = 'ipaddress'
  idipaddress = db.Column( postgresql.UUID, primary_key=True )
  ipaddress = db.Column( postgresql.CIDR, index=True, nullable=False )

      

        
        
        
      

    

I would like to do something like the following:

ip = '192.168.0.0/16'
db.session.query( TableIpAddress.ipaddress.op('<<')(ip) ).all()

      

        
        
        
      

    

This results in the key part of the error message:

sqlalchemy.exc.DBAPIError: 
    (ParameterError) could not pack parameter $1::pg_catalog.inet for transfer

      

        
        
        
      

    

The field is indeed a CIDR field. He doesn't seem to know how to package CIDR. Is there a way to force the parameter to be of the appropriate type?