Django Assign Value To Model Form Before Validate -

i prepared django model form entering information user. made of fields, example, document no., automatically generated if user not enter it.

however, in view method, cannot change field content before validate. field in model mandatory form.is_valid() return false if field leave blank.

so assign value field before form validate failed. need assign value form field before entry form submit view method.

is possible assign value model form before validate? not want change field optional because key field don't want leave blank accidentally.

below example of model , model form:

class example(models.model):     doc_no = models.charfield(max_length = 10)     .     .     .  class exampleform(forms.modelform):     class meta:         model: example         fields: ['doc_no', ...]         widgets = {             'doc_no': forms.textinput(attrs = {....}),             .             .             . 

thanks,

you can do:

class example(models.model): doc_no = models.charfield(max_length = 10, default='enter value here')

this set default value default value here, user's response, if any, override default value.

does help?