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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 checkIsReachable(rh):
 """ Check if a virtual machine is reachable. Input: Request Handle with the following properties: function - 'POWERVM' subfunction - 'ISREACHABLE' userid - userid of the virtual machine Output: Request Handle updated with the results. overallRC - 0: determined the status, non-zero: some weird failure while trying to execute a command on the guest via IUCV rc - RC returned from execCmdThruIUCV rs - 0: not reachable, 1: reachable """


    rh.printSysLog("Enter powerVM.checkIsReachable, userid: " +
        rh.userid)

    strCmd = "echo 'ping'"
    results = execCmdThruIUCV(rh, rh.userid, strCmd)

    if results['overallRC'] == 0:
        rh.printLn("N", rh.userid + ": reachable")
        reachable = 1
    else:
        # A failure from execCmdThruIUCV is acceptable way of determining
        # that the system is unreachable.  We won't pass along the
        # error message.
        rh.printLn("N", rh.userid + ": unreachable")
        reachable = 0

    rh.updateResults({"rs": reachable})
    rh.printSysLog("Exit powerVM.checkIsReachable, rc: 0")
    return 0