generator expression works in shell, NameError in script

[ssc]

Wow! Didn't expect that kind of instant support. Thank you very much,
I'll give both zip and enumerate a try.

The code I've shown is actually copied pretty straight from a Django
form class, but I didn't want to mention that as not to dilute the
conversation. Don't think it matters, anyway. This is the relevant
excerpt:

from django.forms import Form

class SignupForm(Form):

    titles = ['Dr', 'Miss', 'Mr', 'Mrs', 'Ms',]
    title_choices   = [(0, '')] + list((titles.index(t)+1, t) for t in
titles)

Now that I look at it again, it seems odd to me to not have the code
e.g. in __init__(...), but just 'class-global'.
Still, that does not seem a reason for titles not to be not defined,
as I do define it just in the line above.

Does the generator expression have its own little namespace or so ?