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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 readCmd(cls, cmd):
 """run command and return the str format stdout Args: cmd: string Returns: str: what the command's echo """

        args = shlex.split(cmd)
        proc = subprocess.Popen(args, stdout=subprocess.PIPE)
        (proc_stdout, proc_stderr) = proc.communicate(input=None)  # proc_stdin
        return proc_stdout.decode()