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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 broadcastSignal(self, member, signature=None, body=None, path='/org/freedesktop/DBus', interface='org.freedesktop.DBus'):
 """ Sends a signal to all connections with registered interest @type member: C{string} @param member: Name of the signal to send @type path: C{string} @param path: Path of the object emitting the signal. Defaults to 'org/freedesktop/DBus' @type interface: C{string} @param interface: If specified, this specifies the interface containing the desired method. Defaults to 'org.freedesktop.DBus' @type body: None or C{list} @param body: If supplied, this is a list of signal arguments. The contents of the list must match the signature. @type signature: None or C{string} @param signature: If specified, this specifies the DBus signature of the body of the DBus Signal message. This string must be a valid Signature string as defined by the DBus specification. If the body argumnent is supplied , this parameter must be provided. """

        if not isinstance(body, (list, tuple)):
            body = [body]

        s = message.SignalMessage(path, member, interface,
                                  None, signature, body)
        self.router.routeMessage(s)