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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 on_line(client, line):
 """Default handling for incoming lines. This handler will automatically manage the following IRC messages: PING: Responds with a PONG. PRIVMSG: Dispatches the PRIVMSG event. NOTICE: Dispatches the NOTICE event. MOTDSTART: Initializes MOTD receive buffer. MOTD: Appends a line to the MOTD receive buffer. ENDOFMOTD: Joins the contents of the MOTD receive buffer, assigns the result to the .motd of the server, and dispatches the MOTD event. """

    if line.startswith("PING"):
        client.send("PONG" + line[4:])
        return True

    if line.startswith(":"):
        actor, _, line = line[1:].partition(" ")
    else:
        actor = None
    command, _, args = line.partition(" ")
    command = NUMERIC_EVENTS.get(command, command)

    parser = PARSERS.get(command, False)
    if parser:
        parser(client, command, actor, args)
        return True
    elif parser is False:
        # Explicitly ignored message
        return True