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add it to the stack

The rest of the program can’t see

the password variable

The program crashed because, for some reason, the program
couldn’t find a variable called password. But that’s a little odd,
because you define it in the set_password() function:

This code sets the password.
def set_password():
password="C8H10N4O2"
This code uses the
set_password() This code calls for the password to be set. password... but for
some reason, it can’t
def send_to_twitter(msg): see it.
password_manager = urllib.request.HTTPPasswordMgr()
password_manager.add_password("Twitter API",
"http://twitter.com/statuses", "starbuzzceo", password)

So what happened? Why can’t the send_to_twitter()
function see the password variable that was created in the
set_password() function?
Programming languages record variables using a section of
memory called the stack. It works like a notepad. For example,
when the user is asked if she wants to send a price
immediately, her answer is recorded against the
price_now variable:

104 Chapter 3