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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 guest_live_resize_mem(self, userid, size):
 """Live resize memory of guests. :param userid: (str) the userid of the guest to be live resized :param size: (str) The memory size that the guest should have in available status after live resize. The value should be specified by 1-4 bits of number suffixed by either M (Megabytes) or G (Gigabytes). And the number should be an integer. """

        action = "live resize guest '%s' to have '%s' memory" % (userid,
                                                                 size)
        LOG.info("Begin to %s" % action)
        with zvmutils.log_and_reraise_sdkbase_error(action):
            self._vmops.live_resize_memory(userid, size)
        LOG.info("%s successfully." % action)