Cannot import Crypto.Random on python3

[John Nelson]

Crypto/Random/OSRNG/posix.py:66 contains this statement:
     except IOError, e:

This was valid in py2.x, but not in py3.x; consequently the import fails with a SyntaxError:
>>> import Crypto.Random
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/johnn/lib/python/Crypto/Random/__init__.py", line 28, in <module>
    from Crypto.Random import OSRNG
  File "/home/johnn/lib/python/Crypto/Random/OSRNG/__init__.py", line 32, in <module>
    from Crypto.Random.OSRNG.posix import new
  File "/home/johnn/lib/python/Crypto/Random/OSRNG/posix.py", line 66
    except IOError, e:

Version is 2.6 (fetched using PIP a few hours ago).

[Legrandin (gooksankoo)]

You are probably using a python2-enabled pip, so this is not a real bug.

Try this:

===
virtualenv -p /usr/bin/python3 py3
. py3/bin/activate
pip install pycrypto

### Try out the Random module. Some warnings may be presented.
cd py3/lib/python3.2/site-packages/Crypto/SelfTest/Random
python __init__.py
===

[John Nelson (john-nelson2)]

No dice. I didn't have virtualenv installed, so I just got it via "apt-get install python-virtualenv". I am using Ubuntu 12.04 LTS, so it would have just been whatever was in the repo.

After following your steps above, it throws an ImportError on this line:
  File "/home/johnn/lib/python/Crypto/SelfTest/__init__.py", line 35, in <module>
    from StringIO import StringIO

Interestingly, this is yet another 2-3 translation issue (because StringIO now in io module). I also tried re-importing Crypto.Random again from within the virtualenv, but still get the same SyntaxError as before, which doubly suggests a translation issue at install time.

[Legrandin (gooksankoo)]

I was using Ubuntu 12.04 too and it behaved correctly.
Can you post the complete terminal log?

[John Nelson (john-nelson2)]

Attached.

[John Nelson (john-nelson2)]

For clarification, the dpkg and lsb-release stuff on the end of terminal-log.1.txt was a later appendage, but all else was a single shot.

[Sebastian Ramacher (s-ramacher)]

Looking at the log, you seem to get different PyCrypto checkouts mixed up.

(py3)johnn@johnn-ws:~/py3/lib/python3.2/site-packages/Crypto/SelfTest/Random$ python __init__.py

... this is the one that was installed with pip in the virtualenv and converted by 2to3.

  File "/home/johnn/lib/python/Crypto/SelfTest/__init__.py", line 35, in <module>
    from StringIO import StringIO
ImportError: No module named StringIO

... this is a different one. What's your PYTHONPATH? Do you play with sys.path somewhere?

[John Nelson (john-nelson2)]

Good call -- I totally missed that. I did indeed have a path issue pointing to the py2 version.

Feel free to close as a PEBKAC issue. :-/

[Sebastian Ramacher (s-ramacher)]

Closing.