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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def partymode(self):
 """Put all the speakers in the network in the same group, a.k.a Party Mode. This blog shows the initial research responsible for this: http://blog.travelmarx.com/2010/06/exploring-sonos-via-upnp.html The trick seems to be (only tested on a two-speaker setup) to tell each speaker which to join. There's probably a bit more to it if multiple groups have been defined. """

        # Tell every other visible zone to join this one
        # pylint: disable = expression-not-assigned
        [zone.join(self) for zone in self.visible_zones if zone is not self]