def my_generator():
    print("开始")
    yield 1
    print("继续")
    yield 2
    print("结束")
    yield 3

# g = my_generator()   # 注意：此时函数体不会执行！
# print(g,type(g))     # <class 'generator'>
# # print(print,type(print))
# print(next(g))       # 输出：开始 \n 1
# print(next(g))       # 输出：继续 \n 2
# print(next(g))       # 输出：结束 \n 3
# # print(next(g))       # 榨干了

# g2=my_generator()
# for i in g2:
#     print(i)

# print(len(g2))  # 生成器没有len方法


# import time
# def slow_generator():
#     for i in range(5):
#         yield f"第 {i+1} 条数据\n"
#         time.sleep(1)          # 故意慢一点，方便观察
#
# g3=slow_generator()
# for i in g3:
#     print(i)






import json
d=json.dumps('\n\n')
print(d)
# print('1\n\n2')