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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 __live_receivers(signal):
 """Return all signal handlers that are currently still alive for the input `signal`. Args: signal: A signal name. Returns: A list of callable receivers for the input signal. """

    with __lock:
        __purge()
        receivers = [funcref() for funcref in __receivers[signal]]

    return receivers