def get_fields(self):
        """
        This returns a dictionary containing the top most fields,
        ``dates``, ``fields`` and ``queries``.
        """
        field_mapping = OrderedDict()
        for field, data in self.instance.items():
            field_mapping.update(
                {field: self.facet_dict_field_class(
                    child=self.facet_list_field_class(child=self.facet_field_serializer_class(data)), required=False)}
            )

        if self.serialize_objects is True:
            field_mapping["objects"] = serializers.SerializerMethodField()

        return field_mapping 

def compat_serializer_method_field(method_name=None):
    """ method_name changed in DRF > 3. See http://www.django-rest-framework.org/topics/3.0-announcement/#optional-argument-to-serializermethodfield. """
    if DRFVLIST[0] >= 3:
        return serializers.SerializerMethodField()
    else:
        return serializers.SerializerMethodField(method_name=method_name) 

def validate(self, attrs):
        # Because `partial_permissions` is a `SerializerMethodField`,
        # it's read-only, so it's not validated nor added to `validated_data`.
        # We need to do it manually
        self.validate_partial_permissions(attrs)
        return attrs 

def __init__(self, *args, **kwargs):
        self._serializer_method_field = serializers.SerializerMethodField()
        super().__init__(*args, **kwargs) 

def perform_mutate(cls, serializer, info):
        obj = serializer.save()

        kwargs = {}
        for f, field in serializer.fields.items():
            if not field.write_only:
                if isinstance(field, serializers.SerializerMethodField):
                    kwargs[f] = field.to_representation(obj)
                else:
                    kwargs[f] = field.get_attribute(obj)

        return cls(errors=None, **kwargs) 

def get_fields(self):
        field_mapping = OrderedDict()
        field_mapping["facets"] = SerializerMethodField()
        if self.serialize_objects is True:
            field_mapping["objects"] = SerializerMethodField()
        return field_mapping 

def _get_field_type(serializer, field_name, field, include_read_only):
    """
    Try to describe a field type.
    """
    if not include_read_only and hasattr(field, 'writable_doc_format'):
        return _get_type_from_docstring(field.writable_doc_format)

    if hasattr(field, 'doc_format'):
        return _get_type_from_docstring(field.doc_format)

    if isinstance(field, (relations.ManyRelatedField, serializers.ListSerializer)):
        # Many field, recurse on child and make it a list
        if isinstance(field, relations.ManyRelatedField):
            field = field.child_relation
        else:
            field = field.child
        return [_get_field_type(serializer, field_name, field, include_read_only)]

    if field.__class__.__name__ in _SERIALIZER_DEFS:
        return _SERIALIZER_DEFS[field.__class__.__name__]

    if isinstance(field, serializers.SlugRelatedField):
        return _get_details_for_slug(serializer, field_name, field)

    if isinstance(field, serializers.SerializerMethodField):
        # For method fields try to use docstring of the method.
        method_name = field.method_name or 'get_{field_name}'.format(field_name=field_name)
        method = getattr(serializer, method_name, None)
        if method:
            docstring = getattr(method, '__doc__')
            return _get_type_from_docstring(docstring, docstring or 'method')

    if isinstance(field, serializers.BaseSerializer):
        return describe_serializer(field, include_read_only)

    logger = logging.getLogger(__name__)
    logger.error('Undocumented field %s' % field)
    return 'UNKNOWN' 

def setUp(self):
        MockPersonIndex().reindex()
        MockPetIndex().reindex()

        class Serializer1(HaystackSerializer):

            integer_field = serializers.IntegerField()
            city = serializers.SerializerMethodField()

            class Meta:
                index_classes = [MockPersonIndex]
                fields = ["text", "firstname", "lastname", "autocomplete"]

            def get_integer_field(self, instance):
                return 1

            def get_city(self, instance):
                return "Declared overriding field"

        class Serializer2(HaystackSerializer):

            class Meta:
                index_classes = [MockPersonIndex]
                exclude = ["firstname"]

        class Serializer3(HaystackSerializer):

            class Meta:
                index_classes = [MockPersonIndex]
                fields = ["text", "firstname", "lastname", "autocomplete"]
                ignore_fields = ["autocomplete"]

        class Serializer7(HaystackSerializer):

            class Meta:
                index_classes = [MockPetIndex]

        class ViewSet1(HaystackViewSet):
            serializer_class = Serializer1

            class Meta:
                index_models = [MockPerson]

        self.serializer1 = Serializer1
        self.serializer2 = Serializer2
        self.serializer3 = Serializer3
        self.serializer7 = Serializer7
        self.view1 = ViewSet1 

def setUp(self):
        MockPersonIndex().reindex()
        MockPetIndex().reindex()

        class Serializer1(HaystackSerializer):
            """
            Regular multiple index serializer
            """

            class Meta:
                index_classes = [MockPersonIndex, MockPetIndex]
                fields = ["text", "firstname", "lastname", "name", "species", "autocomplete"]

        class Serializer2(HaystackSerializer):
            """
            Multiple index serializer with declared fields
            """
            _MockPersonIndex__hair_color = serializers.SerializerMethodField()
            extra = serializers.SerializerMethodField()

            class Meta:
                index_classes = [MockPersonIndex, MockPetIndex]
                exclude = ["firstname"]

            def get__MockPersonIndex__hair_color(self, instance):
                return "black"

            def get_extra(self, instance):
                return 1

        class Serializer3(HaystackSerializer):
            """
            Multiple index serializer with index aliases
            """

            class Meta:
                index_classes = [MockPersonIndex, MockPetIndex]
                exclude = ["firstname"]
                index_aliases = {
                    'mockapp.MockPersonIndex': 'People'
                }

        class ViewSet1(HaystackViewSet):
            serializer_class = Serializer1

        class ViewSet2(HaystackViewSet):
            serializer_class = Serializer2

        class ViewSet3(HaystackViewSet):
            serializer_class = Serializer3

        self.serializer1 = Serializer1
        self.serializer2 = Serializer2
        self.serializer3 = Serializer3

        self.view1 = ViewSet1
        self.view2 = ViewSet2
        self.view3 = ViewSet3