[Answer]-How to save ForeignKey in queryset? 'NoneType' object has no attribute 'myfield'

What do you get in bookfile ? Is it an object or an id ? If it’s an id, you could try:

bookfile = form.cleaned_data.get('bookfile')
mybook = MyBook.objects.create(number="5555")

bookFileObject = BookFile.objects.create()
bookFileObject.myfile = bookfile
bookFileObject.save()
mybook.file = bookFileObject
mybook.save()