In python, what does len(list) do?

Question

Does len(list) calculate the length of the list every time it is called, or does it return the value of the built-in counter?
I have a context where I need to c

Answer 1

Help on built-in function len in module __builtin__:

len(...)
    len(object) -> integer

    Return the number of items of a sequence or mapping.

so yes, len(list) returns how many items in the list. You might want to describe in more details, providing necessary input files/output to help better understand what you want to do.