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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(self, exe):
 """install callback to executor. Supports installing to multiple exes. Parameters exe : mx.executor.Executor The Executor (returned by symbol.bind) to install to. """

        exe.set_monitor_callback(self.stat_helper, self.monitor_all)
        self.exes.append(exe)