[python] while statement

#example1
unconfirmed_users = ['alice', 'brian', 'candace']
confirmed_users = []

while unconfirmed_users:
    current_user = unconfirmed_users.pop()

    print(f"Verifying User:{current_user.title()}")
    confirmed_users.append(current_user)

print("\nThe following users have been confirmed:")
for confirmed_user in confirmed_users:
    print(confirmed_user.title())
#example2
pets = {'dog','cat','dog','goldfish','cat','rabbit','cat'}
print(pets)
while 'cat' in pets:
    pets.remove('cat')

print(pets)

#example3
responses = {}
polling_active = True
while polling_active:
    name = input("\nWhat is your name?")
    response = input("Which mountain would you like to climb someday?")
    responses[name] = response

    repeat = input("Would you like to let another person respond(yes/no)")
    if repeat == 'no':
        polling_active = False

print("\n--- Poll results ---")
for name,response in responses.items():
    print(f"{name} would like to climb {response}")