'Return a string representation of this C{Deferred}.'

def __str__(self):

    cname = self.__class__.__name__
    result = getattr(self, 'result', _NO_RESULT)
    myID = id(self)
    if (self._chainedTo is not None):
        result = ('    waiting    on    Deferred    at    0x%x' % (id(self._chainedTo),))
    elif (result is _NO_RESULT):
        result = ''
    else:
        result = ('    current    result:    %r' % (result,))
    return ('<%s    at    0x%x%s>' % (cname, myID, result))
