docs: def to_internal_value(self, data):
          """
          Deserialize data from translations fields.
  
          For each received language, delegate validation logic to
          the translation model serializer.
          """
          if data is None:
              return
  
          if not isinstance(data, dict):
              self.fail('invalid')
          if not self.allow_empty and len(data) == 0:
              self.fail('empty')
  
          result, errors = {}, {}
          for lang_code, model_fields in data.items():
              serializer = self.serializer_class(data=model_fields)
              if serializer.is_valid():
                  result[lang_code] = serializer.validated_data
              else:
                  errors[lang_code] = serializer.errors
  
          if errors:
              raise serializers.ValidationError(errors)
          return result