Are Python built-in containers thread-safe?

Question

I would like to know if the Python built-in containers (list, vector, set...) are thread-safe? Or do I need to implement a locking/unlocking environment for my shared variab

Answer 1

Yes, but you still need to be careful of course

For example:

If two threads are racing to pop() from a list with only one item, One thread will get the item successfully and the other will get an IndexError

Code like this is not thread-safe

if L:
    item=L.pop() # L might be empty by the time this line gets executed

You should write it like this

try:
    item=L.pop()
except IndexError:
    # No items left