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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def convert(self, form):
 """ Convert a lazy user to a non-lazy one. The form passed in is expected to be a ModelForm instance, bound to the user to be converted. The converted ``User`` object is returned. Raises a TypeError if the user is not lazy. """

        if not is_lazy_user(form.instance):
            raise NotLazyError('You cannot convert a non-lazy user')

        user = form.save()

        # We need to remove the LazyUser instance assocated with the
        # newly-converted user
        self.filter(user=user).delete()
        converted.send(self, user=user)
        return user