def get_system_ctk(*subdirs):
    """Return path to system-wide cudatoolkit; or, None if it doesn't exist.
    """
    # Linux?
    if sys.platform.startswith('linux'):
        # Is cuda alias to /usr/local/cuda?
        # We are intentionally not getting versioned cuda installation.
        base = '/usr/local/cuda'
        if os.path.exists(base):
            return os.path.join(base, *subdirs)
Return path to system-wide cudatoolkit; or, None if it doesn't exist.
    
numba/cuda/cuda_paths.py