（1）基本实践

分类标签为：鸡、鸭

（2）扩展实践

分类标签为：猫，狗，羊

import os

import shutil

img_folder = "./test"

target_folder = "./target"

img_list = [os.path.join(nm) for nm in os.listdir(img_folder) if nm[-4:] in ['jpeg',]]

for i in img_list: 

    s_path=img_folder + "/" + i

    t_path = target_folder + "/" + i[:-4] + "jpg"

    shutil.copy(s_path, t_path)

=======================

import os

import shutil

img_folder = "./test"

target_folder_t = "./t{}"

img_list = [os.path.join(nm) for nm in os.listdir(img_folder) if nm[-4:] in ['jpeg',]]

count = 1

c = 1

for i in img_list: 

    target_folder = target_folder_t.format(str(c))

    if count % 50 == 0:

        c += 1

    s_path=img_folder + "/" + i

    t_path = target_folder + "/" + i[:-4] + "jpg"

    shutil.copy(s_path, t_path)

    count += 1

=====================================

import pandas as pd

df = pd.read_csv("./demo.csv")

groups = df.groupby("choice") 

groups.count()