'Create a new activation key for the user'

def create_new_activation_key(self, save=True):

    random_string = get_random_string(length=32, allowed_chars=string.printable)
    self.activation_key = hashlib.sha1(random_string.encode(u'utf-8')).hexdigest()
    if save:
        self.save()
    return self.activation_key
