old_contents: """
  Base webhook implementation
  """
  import json, copy
  
  from django.http import HttpResponse
  from django.views.generic import View
  
  from django.utils.decorators import method_decorator
  from django.views.decorators.csrf import csrf_exempt
  
  
  class WebhookBase(View):
  
      @method_decorator(csrf_exempt)
      def dispatch(self, request, *args, **kwargs):
          return super(WebhookBase, self).dispatch(request, *args, **kwargs)
  
      def post(self, request, *args, **kwargs):
          data = json.loads(request.body.decode('utf-8'))
          meta = copy.copy(request.META)
  
          for k, v in meta.items():
              if not isinstance(v, basestring):
                  del meta[k]
  
          try:
              self.process_webhook(data, meta)
          except Exception:
              self.handle_exception()
  
          return HttpResponse(status=200)
  
      def process_webhook(self, data, meta):
          raise NotImplementedError
      
      def handle_exception(self, data, meta):
          pass
  
new_contents: """
  Base webhook implementation
  """
  import json, copy
  
  from django.http import HttpResponse
  from django.views.generic import View
  
  from django.utils.decorators import method_decorator
  from django.views.decorators.csrf import csrf_exempt
  
  
  class WebhookBase(View):
  
      @method_decorator(csrf_exempt)
      def dispatch(self, request, *args, **kwargs):
          return super(WebhookBase, self).dispatch(request, *args, **kwargs)
  
      def post(self, request, *args, **kwargs):
          data = json.loads(request.body.read().decode('utf-8'))
          meta = copy.copy(request.META)
  
          for k, v in meta.items():
              if not isinstance(v, basestring):
                  del meta[k]
  
          try:
              self.process_webhook(data, meta)
          except Exception:
              self.handle_exception()
  
          return HttpResponse(status=200)
  
      def process_webhook(self, data, meta):
          raise NotImplementedError
      
      def handle_exception(self, data, meta):
          pass
  
subject: Update base.py