Well south with custom fields can be a mess, introspection rules basically tell south what and how properties translate to constructor arguments. For example to constructor argument from ForeignKey translates to property field.rel.to . Moreover you define introspections for fields and not for models.
You have such field class and you want to make it work with south --- problem is with default_callable argument that is a callable and cannot be frozen.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.