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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 runCommandReturnOutput(cmd):
 """ Runs a shell command and return the stdout and stderr """

    splits = shlex.split(cmd)
    proc = subprocess.Popen(
        splits, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    stdout, stderr = proc.communicate()
    if proc.returncode != 0:
        raise subprocess.CalledProcessError(stdout, stderr)
    return stdout, stderr