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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def handle_ajax_method(self, request, method):
 """handle ajax methods and return serialized reponse in the default state allows only authentificated users - Depends on method parameter render whole region or single widget - If widget_id is present then try to load this widget and call method on them - If class_name is present then try to load class and then call static method on this class - If class_name is present then try to load class and if method_name == render_preview then render widget preview without instance """


        response = {}

        def get_param(request, name):

            try:
                return request.POST[name]
            except KeyError:
                return request.GET.get(name, None)

        widget_id = get_param(request, "widget_id")
        class_name = get_param(request, "class_name")

        if method in 'widget_content':
            return self.render_widget(request, widget_id)

        if method == 'region':
            return self.render_region(request)

        # handle methods called directly on widget
        if widget_id:

            widget = get_widget_from_id(widget_id)

            try:
                func = getattr(widget, method)
            except AttributeError:
                response["exception"] = "%s method is not implmented on %s" % (
                    method, widget)
            else:
                response["result"] = func(request)

        elif class_name:
            # handle calling classmethod without instance

            try:
                cls = get_model(*class_name.split('.'))
            except Exception as e:
                response["exception"] = str(e)
                return JsonResponse(data=response)

            if method == "render_preview":

                # TODO: i think that we need only simple form
                # for loading relations but maybe this would be need it
                # custom_form_cls = getattr(
                #     cls, 'feincms_item_editor_form', None)

                # if custom_form_cls:
                #     FormCls = modelform_factory(cls, form=custom_form_cls,
                #                                 exclude=('pk', 'id'))

                FormCls = modelform_factory(cls, exclude=('pk', 'id'))

                form = FormCls(request.POST)

                if form.is_valid():

                    widget = cls(**form.cleaned_data)

                    request.frontend_editing = False

                    try:
                        content = widget.render(**{'request': request})
                    except Exception as e:
                        response['result'] = widget.handle_exception(request, e)
                    else:
                        response['result'] = content

                    response['id'] = widget_id

                else:
                    response['result'] = form.errors
                    response['id'] = widget_id

            else:
                # standard method
                try:
                    func = getattr(cls, method)
                except Exception as e:
                    response["exception"] = str(e)
                else:
                    response["result"] = func(request)

        return JsonResponse(data=response)