Nested.default — incorrect documentation

[Inego]

Nested field documentation says that the default parameter may be used to serialize None values:
:param default: Default value to if attribute is missing or None
However, this does not correspond to reality: default values are only used to serialize missing fields. And it seems that there is no way to make the default value be used for serialization of None values — by fine-tuning the field parameters, at least.

[sloria]

Good catch. I've removed the default documentation for Nested because the semantics are the same as Field.