type SpaceSeparatedList

Serializes ``value`` to a basic Python datatype. Noop by default. Concrete :class:`Field` classes should implement this method.

Example: :

   class TitleCase(Field):
       def _serialize(self, value, attr, obj):
           if not value:
               return ''
           return unicode(value).title()

:param value: The value to be serialized. :param str attr: The attribute or key on the object to be serialized. :param object obj: The object the value was pulled from. :raise ValidationError: In case of formatting or validation failure. :return: The serialized value

Overrides: marshmallow.base.FieldABC._serialize

Deserialize value. Concrete :class:`Field` classes should implement this method.

:param value: The value to be deserialized.
:param str attr: The attribute/key in `data` to be deserialized.
:param dict data: The raw input data passed to the `Schema.load`.
:raise ValidationError: In case of formatting or validation failure.
:return: The deserialized value.

.. versionchanged:: 2.0.0
    Added ``attr`` and ``data`` parameters.

Overrides: marshmallow.base.FieldABC._deserialize