Why am I getting a NameError?

Question

I have the following code: ``` from crypt import crypt from itertools import product from string import ascii_letters, digits def decrypt(all_hashes, salt, charset=ascii_letters + digits + "-"): products = (product(charset, repeat=r) for r in range(8)) chain = itertools.chain.from_iterable(products) for candidate in chain: hash = crypt(candidate, salt) if hash in all_hashes: yield candidate, hash all_hashes.remove(hash) if not all_hashes: return all_hashes = ['aaRrt6qwqR7xk', 'aaacT.VSMxhms' , 'aaWIa93yJI9kU', 'aakf8kFpfzD5E', 'aaMOPiDnXYTPE', 'aaz71s8a0SSbU', 'aa6SXFxZJrI7E' 'aa9hi/efJu5P.', 'aaBWpr07X4LDE', 'aaqwyFUsGMNrQ', 'aa.lUgfbPGANY' 'aaHgyDUxJGPl6', 'aaTuBoxlxtjeg', 'aaluQSsvEIrDs', 'aajuaeRAx9C9g' 'aat0FraNnWA4g', 'aaya6nAGIGcYo', 'aaya6nAGIGcYo', 'aawmOHEectP/g' 'aazpGZ/jXGDhw', 'aadc1hd1Uxlz.', 'aabx55R4tiWwQ', 'aaOhLry1KgN3.' 'aaGO0MNkEn0JA', 'aaGxcBxfr5rgM', 'aa2voaxqfsKQA', 'aahdDVXRTugPc' 'aaaLf47tEydKM', 'aawZuilJMRO.w', 'aayxG5tSZJJHc', 'aaPXxZDcwBKgo' 'aaZroUk7y0Nao…

Accepted Answer

It doesn't look like you imported `itertools`...

```
from itertools import product
```

doesn't count as that will only pull `product` directly into your module's namespace (your module still doesn't know anything about the rest of `itertools`. Just add:

```
import itertools
```

at the top of your script and that error should go away because now you've pulled the `itertools` namespace into your module's namespace under the name `itertools`. In other words, to have access to the `chain` function, you'd use `itertools.chain` (as you have in your script above).

Why am I getting a NameError?

Solution

Problem