                              self.object = None
                          else:
                              self.object = identity_to_objects.pop(identity, None)
  
                      ret.append(self.from_native(item, None))
                      errors.append(self._errors)
  
                  if update:
                      self._deleted = identity_to_objects.values()
                  self._errors = any(errors) and errors or []
              else:
 
</s> remove                 if update:
                    self._deleted = identity_to_objects.values()
                self._errors = any(errors) and errors or []
 </s> add                     self._errors = any(errors) and errors or [] </s> remove                 for item in data:
                    if update:
                        # Determine which object we're updating
                        try:
                            identity = self.get_identity(item)
                        except:
                            self.object = None
                        else:
                            self.object = identity_to_objects.pop(identity, None)
 </s> add                 try:
                    iter(data)
                    if isinstance(data, dict):
                        raise TypeError
                except TypeError:
                    self._errors = {'non_field_errors': ['Expected a list of items']}
                else:
                    for item in data:
                        if update:
                            # Determine which object we're updating
                            try:
                                identity = self.get_identity(item)
                            except:
                                self.object = None
                            else:
                                self.object = identity_to_objects.pop(identity, None)

                        ret.append(self.from_native(item, None))
                        errors.append(self._errors) </s> remove         Correct bulk update serialization should return the input data.
 </s> add         Incorrect bulk update serialization should return error data.
                    if update:
                        self._deleted = identity_to_objects.values()
                              self.object = None
                          else:
                              self.object = identity_to_objects.pop(identity, None)
  
                    if update:
                        self._deleted = identity_to_objects.values()
                    if update:
                        self._deleted = identity_to_objects.values()
  
                  if update:
                      self._deleted = identity_to_objects.values()
                  self._errors = any(errors) and errors or []
              else:
keep keep keep keep replace replace keep keep keep keep keep
 Add extra tests for errors from incorrect data with multiple create/update 
rest_framework/serializers.py