def a():
while True:
print('哈哈')
yield None
def b():
while True:
print('嘿嘿')
yield None
x1 = a()
x2 = b()
while True:
next(x1)
next(g2)
def a():
while True:
print('哈哈')
yield None
def b():
while True:
print('嘿嘿')
yield None
x1 = a()
x2 = b()
while True:
next(x1)
next(g2)