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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 _autodetect_num_gpus():
 """Attempt to detect the number of GPUs on this machine. TODO(rkn):
 This currently assumes Nvidia GPUs and Linux. Returns: The number of GPUs if any were detected, otherwise 0. """

    proc_gpus_path = "/proc/driver/nvidia/gpus"
    if os.path.isdir(proc_gpus_path):
        return len(os.listdir(proc_gpus_path))
    return 0