[Answered ]-Django save(commit=False) versus full_clean

Calling full_clean() is the correct way to validate a model instance.

from django.core.exceptions import ValidationError

try:
    obj.full_clean()
except ValidationError:
    # handle invalid object

When dealing with a model form, calling is_valid() will perform the model validation, so you don’t have to call full_clean() manually.

Calling save() with commit=False doesn’t perform model validation. Instead, it gives you the opportunity to change the object before you save it to the database. A common example is to set the user attribute to the user that is currently logged on.