docs: def get_fields(self):
          """Dynamically adapt fields based on the current request."""
          fields = super(CollectionSerializer, self).get_fields()
  
          if self.request.method == "GET":
              fields['data'] = serializers.SerializerMethodField()
          else:
              fields['data'] = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
  
          return fields