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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 join(self, target, key=None):
 """Attempt to join a channel. The optional second argument is the channel key, if needed. """

        chantypes = self.server.features.get("CHANTYPES", "#")
        if not target or target[0] not in chantypes:
            # Among other things, this prevents accidentally sending the
            # "JOIN 0" command which actually removes you from all channels
            _log.warning("Refusing to join channel that does not start "
                         "with one of '%s': %s", chantypes, target)
            return False

        if self.server.in_channel(target):
            _log.warning("Ignoring request to join channel '%s' because we "
                         "are already in that channel.", target)
            return False

        _log.info("Joining channel %s ...", target)
        self.send("JOIN", target, *([key] if key else []))
        return True