Remove getCallback indirection in modules Instead, assume that the imported module contains the Callback class that was previously returned by getCallback. This is done to prevent a circular import (caused by the __init__ importing a submodule).

from query import *
from subqueries import *
from where import AND, OR
from datastructures import EmptyResultSet

__all__ = ['Query', 'AND', 'OR', 'EmptyResultSet']