code: def activation_key_expired(self):
          
  
          # utils imported here to avoid circular import
          import utils
  
          expiration_date = datetime.timedelta(
              days=utils.get_settings('REGISTRATION_API_ACCOUNT_ACTIVATION_DAYS'))
          return self.activation_key == self.ACTIVATED or \
              (self.user.date_joined + expiration_date <= datetime_now())
docs: Determine whether this ``RegistrationProfile``'s activation
          key has expired, returning a boolean -- ``True`` if the key
          has expired.
          Key expiration is determined by a two-step process:
          1. If the user has already activated, the key will have been
          reset to the string constant ``ACTIVATED``. Re-activating
          is not permitted, and so this method returns ``True`` in
          this case.
  
          2. Otherwise, the date the user signed up is incremented by
          the number of days specified in the setting
          ``REGISTRATION_API_ACCOUNT_ACTIVATION_DAYS`` (which should be
          the number of days after signup during which a user is allowed
          to activate their account); if the result is less than or
          equal to the current date, the key has expired and this method
          returns ``True``.