class PostFilter(django_filters.FilterSet):
    latitude = django_filters.NumberFilter(field_name='latitude', method='filter_latitude')
    longitude = django_filters.NumberFilter(field_name='longitude', method='filter_longitude')

    class Meta:
        model = Post
        fields = ['latitude', 'longitude', 'country', 'state', 'district', ]

    def filter_latitude(self, qs, latitude, value):
        try:
            return qs.filter(Q(latitude__gte=value - 2) & Q(latitude__lte=value + 2))
        except BaseException:
            return qs

    def filter_longitude(self, qs, longitude, value):
        try:
            return qs.filter(Q(longitude__gte=value - 2) & Q(longitude__lte=value + 2))
        except BaseException:
            return qs