Django - saving fields in invalid form submissions
You will need to provide your own clean method to deal with the non-validating fields, and prevent cleaned_data being clobbered.
You will need to also provide your own save method which knows to only save the right fields.
What is the recommended way of handling a "save"-style form submission (created from a ModelForm) when:

A non-empty subset of the form's fields validate
A non-empty subset of the form's fields do not validate
I want to save the subset of fields that are valid to the instance in question, and not the invalid ones.

I'm fairly sure I could write the code to do this but as with much of Django I'm sure there's a "normal"/"recommended" way of solving this, or some pattern I can follow.
All advice much appreciated.