This has been added to the official documentation: https://bitbucket.org/zzzeek/sqlalchemy/issue/3046/postgresql-range-types-need-better
Had to dig around for this, but when in doubt, check the tests! The SQLAlchemy tests for the range types use the underlying psycopg2 types.
from psycopg2.extras import NumericRange
from sqlalchemy import create_engine, Column, Integer
from sqlalchemy.dialects.postgresql import INT4RANGE
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
engine = create_engine('postgresql:///example', echo=True)
Session = sessionmaker(bind=engine)
session = Session()
Base = declarative_base(bind=engine)
class Example(Base):
__tablename__ = 'example'
id = Column(Integer, primary_key=True)
window = Column(INT4RANGE, nullable=False)
Base.metadata.create_all()
session.add(Example(window=NumericRange(2, 6)))
session.add(Example(window=NumericRange(4, 8)))
session.commit()