def list_articles(dir, extension):
    "lists all articles in current dir and below"
    try:
        DEVNULL = open(os.devnull, 'wb')
        listing = subprocess.check_output(["tree", dir], stderr=DEVNULL)
        listing = remove_fileextension(listing, extension)
        print(listing)
    except __HOLE__:
        print("Error: tree not installed")
        return False
    except subprocess.CalledProcessError:
        print("Error: File or Directory not found")
dataset/ETHPy150Open noqqe/cmddocs/cmddocs/articles.py/list_articles