Question

I have this code from Learn Python The Hard Way and I need to comment it:

from sys import argv

So I did: #imports argv from the sys module

I know what argv does, but I am having trouble figuring out what to call this element of the sys module? A variable, a method, a function? Argument variable?

Also, given that line of code, does it mean that all the sys module is imported in my program or only argv?

Answer 1

argv is a variable in the sys module’s namespace. It happens to be a list.

The statement

from sys import argv

causes Python to parse the entire sys module (assuming it has not already been parsed, in which case it is not reloaded), and copy the argv variable into the current module’s namespace.