How to override multiplechoicefilter so that it filters not only by all selected values, but also by an additional parameter?

Question

Django

I'm using djano-filter to filter on specific fields. My model has a region field which I filter using multiplechoicefilter. Everything works correctly, if I select several areas, then everything works correctly.
But I need to expand the operation of this method so that it searches not only by value, but also so that if the database contains the word "any" instead of a certain region, then it takes this into account. That is, if a person selects the "Moscow" district, then he will display records where both "Moscow" and "any" are written. I did not find in the documentation how this can be done with this filter.

I tried to set my own method , but without success. When I had just choicefilter , instead of multiple , everything worked out. Here I don't know how to do it.

class DailyOrdersFilter(django_filters.FilterSet):
    STATUS_CHOICES4 = (
        ('Советский', 'Советский'),
        ('Приволжский', 'Приволжский'),

    district_kazan = django_filters.MultipleChoiceFilter(field_name='district', choices=STATUS_CHOICES4,
                                                         label='Требуемый район', lookup_expr='icontains')

I tried to go down inside multiplechoicefilter and it says that this method can be overridden by changing the class "get_filter_predicate"

def get_filter_predicate(self, v):
        name = self.field_name
        if name and self.lookup_expr != settings.DEFAULT_LOOKUP_EXPR:
            name = LOOKUP_SEP.join([name, self.lookup_expr])
        try:
            return {name: getattr(v, self.field.to_field_name)}
        except (AttributeError, TypeError):
            return {name: v}

But I don't quite understand how. Help me please!