class FilterKeyDoesNotExis Exception pass class FilterUnknownBinding E

    class FilterKeyDoesNotExist(Exception):
        pass

    class FilterUnknownBinding(Exception):
        pass

    class Filter(object):
        def __init__(self, conditions):
            self.conditions = conditions

        def __parse_conditions(self, x):
            
            binding = unicode(x['binding'], 'utf8')
            operator = unicode(x['op'], 'utf8')
            key = getattr(TChartAttributes, x['fieldId'].lower(), None)
            value = unicode(x['value'], 'utf8')

            if key is None:
                raise FilterKeyDoesNotExist(u"Field doesn't exist.")

            if binding == 'and':
                binding_callback = and_
            elif binding == 'or':
                binding_callback = or_
            else:
                raise FilterUnknownBinding(u'Unknown binding detected.')

            if operator == '=':
                return binding_callback(key == value)
            else:
                return bindind_callback(key != value)

        def get_filters(self):
            filters = []
            for x in self.conditions:
                filters.append(self.__parse_conditions(x))
            return filters