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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 broadcast_channel(message, channel):
 """ Find the first socket for the given channel, and use it to broadcast to the channel, including the socket itself. """

    try:
        socket = CLIENTS[CHANNELS.get(channel, [])[0]][1]
    except (IndexError, KeyError):
        raise NoSocket("There are no clients on the channel: " + channel)
    socket.send_and_broadcast_channel(message, channel)