如何放置一个循环，要求用户一次又一次地输入直到输入正确的国家/地区

Question

how to put a loop that asks user again and again to input till it enters correct country

population ={
    'china': '143',
    'india': '136',
    'usa': '32',
    'pakistan': '21'
}
population['bhutan'] = 2

print(population['china'])


country = input("enter countri name-")
country.lower()
if country in population:
    print(f"population {country} is: {population[country]} crore")
else:
   print("input again")
   country = input("enter countri name-")

if country in population:
    print(f"population {country} is: {population[country]} crore")
else:
   print("input again")

Answer 1

One way to do is with a while true that check if the input is correct using the break keyword that will stop the loop

while True:
   country = input("enter countri name-")
   if country in population:
        break;
    

Or even do something like this that is more pythonic

country = input("enter countri name-")
while country not in population:
   country = input("Enter valid country")