Really weird.

I know the module is installed, as I can perfectly check on command line using interactive python interpreter:

sh-3.2# python

Python 2.7.8 (default, Jul 13 2014, 17:11:32) 
[GCC 4.2.1 Compatible Apple LLVM 5.1 (clang-503.0.40)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import qrcode
>>> help (qrcode)
Help on package qrcode:

NAME
    qrcode

FILE
    /opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/qrcode-5.0.1-py2.7.egg/qrcode/__init__.py

But activating "hw_escpos" module within Odoo, always throws the following error:

Error
Unable to install module "hw_escpos" because an external dependency is not met: No module named qrcode

Any idea why this might be happening?