In a Django form, how do I make a field readonly (or disabled) so that it cannot be edited?

Question

In a Django form, how do I make a field read-only (or disabled)?

When the form is being used to create a new entry, all fields should be enabled - but when the recor

Answer 1

As I can't yet comment (muhuk's solution), I'll response as a separate answer. This is a complete code example, that worked for me:

def clean_sku(self):
  if self.instance and self.instance.pk:
    return self.instance.sku
  else:
    return self.cleaned_data['sku']