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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 install(cls, mbox):
 """A decorator to indicate a remotely callable method on a process. .. code-block:: python from compactor.process import Process class PingProcess(Process):
 @Process.install('ping') def ping(self, from_pid, body):
 # do something The installed method should take ``from_pid`` and ``body`` parameters. ``from_pid`` is the process calling the method. ``body`` is a ``bytes`` stream that was delivered with the message, possibly empty. :param mbox: Incoming messages to this "mailbox" will be dispatched to this method. :type mbox: ``str`` """

    def wrap(fn):
      setattr(fn, cls.INSTALL_ATTRIBUTE, mbox)
      return fn
    return wrap