@classmethod
def _from_json(cls, parsed):
    ticket = parsed.get(_TICKET)
    if (not ticket):
        raise ValueError(('%s not set' % _TICKET))
    return cls(parsed, ticket, parsed.get(_WORKER_ID))
@classmethod
def _from_json(cls, parsed):
    ticket = parsed.get(_TICKET)
    if (not ticket):
        raise ValueError(('%s not set' % _TICKET))
    return cls(parsed, ticket, parsed.get(_WORKER_ID))