  
          if isinstance(model_field, models.AutoField) or not model_field.editable:
              kwargs['read_only'] = True
  
          if model_field.has_default():
              kwargs['required'] = False
              kwargs['default'] = model_field.get_default()
  
          if issubclass(model_field.__class__, models.TextField):
              kwargs['widget'] = widgets.Textarea
  
 
</s> remove         kwargs['blank'] = model_field.blank

        if model_field.null or model_field.blank:
 </s> add         if model_field.null or model_field.blank or has_default: </s> remove     target = serializers.SlugRelatedField(slug_field='name', null=True)
 </s> add     target = serializers.SlugRelatedField(slug_field='name', required=False) </s> remove             title = serializers.CharField(blank=True)
 </s> add             title = serializers.CharField(required=False)
        if has_default:
  
          if isinstance(model_field, models.AutoField) or not model_field.editable:
              kwargs['read_only'] = True
  
        if has_default:
        if has_default:
              kwargs['default'] = model_field.get_default()
  
          if issubclass(model_field.__class__, models.TextField):
              kwargs['widget'] = widgets.Textarea
  
keep keep keep keep replace replace keep keep keep keep keep
 Use new style of `required=<bool>` not `blank` or `null` 
rest_framework/serializers.py