[Fixed]-Assertion fails with same object

Since your instances are not saved, the model instance returned by form.save with commit=False and the original unsaved object will never be equal (except you override the __eq__ method of your model to handle this):

From the docs:

The equality method is defined such that instances with the same
primary key value and the same concrete class are considered equal,
except that instances with a primary key value of None aren’t equal to anything except themselves