def queryFilter(self, function=None):
if function is not None:<EOL><INDENT>self.__query_filter = function<EOL>return function<EOL><DEDENT>def wrapper(func):<EOL><INDENT>self.__query_filter = func<EOL>return func<EOL><DEDENT>return wrapper<EOL>
Defines a decorator that can be used to filter
queries.  It will assume the function being associated
with the decorator will take a query as an input and
return a modified query to use.

:usage

    class MyModel(orb.Model):
        objects = orb.ReverseLookup('Object')

        @classmethod
        @objects.queryFilter()
        def objectsFilter(cls, query, **context):
            return orb.Query()

:param function: <callable>

:return: <wrapper>