要查找最短的文件，只需与当前最短的文件进行比较：

chosen_file = ""

for file in glob.glob("*.txt"):
    if chosen_file == "" or len(file) < len(chosen_file):
        chosen_file = file

print(f"{chosen_file} is the shortest file")

一旦完成循环，chosen_file str就一定是最短的。

将其放入函数中并调用它：

import glob
import os

def shortest_file_name(inpDir: str, extension: str) -> str:
    os.chdir(inpDir)
    shortest, l = '', 0b100000000
    for file in glob.glob(extension):
        if len(file) < l:
            l = len(file)
            shortest = file
    return shortest

inpDir = "C:/Users/ft/Desktop/Folder"
min_file_name = shortest_file_name(inpDir, "*.txt")

只需使用glob模块获取文件列表，然后利用min(..., key=...)查找最短的字符串（请参见help(min)）：

min(glob.glob('*.txt'), key=len)

min = 1000

for file in glob.glob("*.txt"):
    if len(file) < min:
        min = len(file)
        name = file