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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 ajax(authenticated=True, data_required=False, json_encoder=json.JSONEncoder):
 """Decorator to allow the wrappered view to exist in an AJAX environment. Provide a decorator to wrap a view method so that it may exist in an entirely AJAX environment: - data decoded from JSON as input and data coded as JSON as output - result status is coded in the HTTP status code; any non-2xx response data will be coded as a JSON string, otherwise the response type (always JSON) is specific to the method called. if authenticated is true then we'll make sure the current user is authenticated. If data_required is true then we'll assert that there is a JSON body present. The wrapped view method should return either: - JSON serialisable data - an object of the django http.HttpResponse subclass (one of JSONResponse or CreatedResponse is suggested) - nothing Methods returning nothing (or None explicitly) will result in a 204 "NO CONTENT" being returned to the caller. """

    def decorator(function, authenticated=authenticated,
                  data_required=data_required):
        @functools.wraps(function,
                         assigned=decorators.available_attrs(function))
        def _wrapped(self, request, *args, **kw):
            if authenticated and not request.user.is_authenticated:
                return JSONResponse('not logged in', 401)
            if not request.is_ajax():
                return JSONResponse('request must be AJAX', 400)

            # decode the JSON body if present
            request.DATA = None
            if request.body:
                try:
                    request.DATA = jsonutils.loads(request.body)
                except (TypeError, ValueError) as e:
                    return JSONResponse('malformed JSON request: %s' % e, 400)

            if data_required:
                if not request.DATA:
                    return JSONResponse('request requires JSON body', 400)

            # invoke the wrapped function, handling exceptions sanely
            try:
                data = function(self, request, *args, **kw)
                if isinstance(data, http.HttpResponse):
                    return data
                elif data is None:
                    return JSONResponse('', status=204)
                return JSONResponse(data, json_encoder=json_encoder)
            except http_errors as e:
                # exception was raised with a specific HTTP status
                for attr in ['http_status', 'code', 'status_code']:
                    if hasattr(e, attr):
                        http_status = getattr(e, attr)
                        break
                else:
                    LOG.exception('HTTP exception with no status/code')
                    return JSONResponse(str(e), 500)
                return JSONResponse(str(e), http_status)
            except Exception as e:
                LOG.exception('error invoking apiclient')
                return JSONResponse(str(e), 500)

        return _wrapped
    return decorator