'Return a compare operation for the columns represented by
this ``MapperProperty`` to the given value, which may be a
column value or an instance.  \'operator\' is an operator from
the operators module, or from sql.Comparator.
By default uses the PropComparator attached to this MapperProperty
under the attribute name "comparator".'

def compare(self, operator, value, **kw):

    return operator(self.comparator, value)
