在 Python 中将字典输出为字符串

Question

Looking at the print statements in the following format, it's also required to include any new countries and population entered as input. I can make the code to show an appended dictionary in a dict format but having a hard time showing in the following format. What am I doing incorrectly?

Expected Output:

 Vatican has Population 800 Vatican has Population 10200 ...

def main():
        countryPop = {'Vatican': 800, 'Tuvalu': 10200, 'Nauru': 11000, 'Palau': 17900,
                      'San Marino': 33420, 'Monaco': 38300, 'Marshall Islands': 55500}

        # while loop to repeat the input request and population display until 0 is entered
        while True:
            ctry = input('Enter country:')
            population = countryPop.get(ctry)
            print('Population:',population)
            if ctry == '0':
                break

            # Else if Loop meant to activate if a country unknown to the original dictionary is entered
            elif ctry not in countryPop:
                popIn = input("Country Pop:")
                countryPop[ctry] = popIn

        # printing the new list after breaking from the loop
        for ctry in countryPop:
            print(str(ctry)+" has population "+str(popIn))
    if __name__ == '__main__':
        main()

Answer 1

You can use the for key in dict syntax to iterate over a dictionary's keys. Then, inside your loop, you can use dict[key] to read what's saved in that key. So the following would work:

countryPop = {'Vatican': 800, 'Tuvalu': 10200, 'Nauru': 11000, 'Palau': 17900,
                      'San Marino': 33420, 'Monaco': 38300, 'Marshall Islands': 55500}

for key in countryPop:
    print(key + " has Population " + str(countryPop[key]))

Output:

Palau has Population 17900

Tuvalu has Population 10200

Vatican has Population 800

San Marino has Population 33420

Marshall Islands has Population 55500

Monaco has Population 38300

Nauru has Population 11000

Answer 2

This will print what you want

for ctry, pop in countryPop.items():
    print(f"{ctry} has population {pop}")