while 条件：
代码块
print()
定时器：import time ，time.sleep(1),等待1秒
n=True
while n:
print('1')
time.sleep(1)
n=False
print('end')
=============================================
import time
kaishi = 1
flag=True
while flag:
print(kaishi)
if kaishi == 10
flag=false
kaishi=kaishi + 1
time.sleep(1)
print('end')
============================================
break ---用于跳出循环
kaishi =1
while True:
print(kaishi)
if kaishi ==10
break
kaishi = kaishi +1
============================================
continue---用于跳出本次循环，继续下次循环
while True:
print('123')
continue
print('456')
只能输入123，一直输出，而不能输出456
==========================================
输出1到10
start = 1
while True:
print(start)
if start == 10:
break
#start = start + 1
start +=1
==========================================
输出1 2 3 4 5 6 8 9 10
start = 1
while True:
if start ==7:
start +=1
continue
print(start)
if start == 10:
break
#start = start + 1
start +=1
==========================================
1 到 100 所有数的和
i=1
sum=0
while true：
print(i)
sum = sum + i
if i ==100:
break
i=i+1
print(sum)
==========================================
1 到 100 所有奇数的和
i=1
sum=0
while true：
print(i)
if i % 2 ==1：
sum = sum + i
if i ==100:
break
i=i+1
print(sum)
==========================================
1 到 100 所有偶数的和
i=1
sum=0
while true：
print(i)
if i % 2 ==0：
sum = sum + i
if i ==100:
break
i=i+1
print(sum)