This exception is thrown into listeners for IQ responses by aioxmpp.stream.StanzaStream if a response for an IQ was received, but could not be decoded (due to malformed or unsupported payload).
An exception subclass, which should be used as a mix-in.
It is intended to be used for exceptions which may be user-facing, such as connection errors, value validation issues and the like.
localizable_string must be a i18n.LocalizableString instance. The args and kwargs will be passed to LocalizableString.localize when either str() is called on the UserError or localize() is called.
The str() is created using the default LocalizingFormatter and a gettext.NullTranslations instance. The point in time at which the default localizing formatter is created is unspecified.
This is a ValueError with UserError mixed in.