'Difference to Greenwich time in hours; e.g. \'+0200\', \'-0430\''

def O(self):

    seconds = self.Z()
    sign = (u'-' if (seconds < 0) else u'+')
    seconds = abs(seconds)
    return (u'%s%02d%02d' % (sign, (seconds // 3600), ((seconds // 60) % 60)))
