[Python] Why does modifying a list during iteration with a for loop not work as intended in...

I encountered an issue where I intended to limit the invitations to only two people using a for loop. However, the code ends up leaving three people in the list instead of two. Here's the code I'm using:

print('Unfortunately you are allowed to invite only two people')

people_to_invite = ['leonardo da vinci', 'jorden b peterson', 'jeffrey kaplan', 'joshua meyer', 'harold', 'james bon', 'jakie chan']

for people in people_to_invite:
if len(people_to_invite) > 2:
place_holder = people_to_invite.pop()
else:
break

for person in people_to_invite:
print(f">>Dear {person.title()}, I would like to invite you to a dinner gathering at my home on Saturday,\nthe 15th, at 7 PM. It would be wonderful to have you with us!")


This part of the code is meant to remove people until only two remain:

for people in people_to_invite:
if len(people_to_invite) > 2:
place_holder = people_to_invite.pop()
else:
break


However, it doesn't work as expected. The result is that three people remain in the list. I know I can use a while loop instead, like this:

while len(people_to_invite) > 2:
people_to_invite.pop()


Or, I can modify the logic using:

for people in range(len(people_to_invite) - 2):
place_holder = people_to_invite.pop()


But I’m curious—what exactly is causing the issue with the original for loop? Is there an underlying limitation of the for loop when modifying a list during iteration?

Any clarification would be greatly appreciated!

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