How to fix ‘ImportError: No module named X’ in Python

Jan Jarfalk — Fri, 24 Oct 2008 21:56:23 +0000

The problem is your python path, or rather the lack of one. You need to set environment variable PYTHONPATH to the absolute path of the missing module. One way of doing it is to append the path with in python.

import sys
sys.path.append('/path/to/module')

Here is example from the real world. When I tried to compress the Netflixprize dataset using the pythonscript pyflix it returned this error.

Traceback (most recent call last):
  File "pyflix/setup.py", line 13, in 
    from pyflix import timeCall
ImportError: No module named pyflix

My solution to the problem was to add two lines of code in the beginning of setup.py. Notice the import on line seven and the appending of a path on line eight.

#!/usr/bin/env python

'''Script for generating the indexed binary datasets.'''

#==== imports ==================================================================

import sys
sys.path.append('/users/janjarfalk/projects/netflixprize/pyflix-0.1')

import cPickle
from operator import itemgetter
from optparse import OptionParser, make_option

import numpy as N

from pyflix import timeCall

How to install mysql-python on Apple OS X Leopard

Jan Jarfalk — Wed, 22 Oct 2008 21:49:58 +0000

When I tried to build and install mysql-python, on my Macbook Pro running Apple OS X Leopard 10.5.5, I encountered a few problems (Setup script exited with error: command ‘gcc’ failed with exit status 1). But thanks to Google and the Python community, there were no problems that couldn’t be fixed.

Step 1 – Download and extract mysql-python

Let’s take it from the top. First you need to download mysql-python from the Sourceforge project page and extract the files.

Step 2 – Locate and edit _mysql.c

Locate the _mysql.c file in your mysql-python directory, open it up and remove the following three rows around row 35.

#ifndef uint
#define uint unsigned int
#endif

Still in _mysql.c, you should change the following two rows around row 480.

uint port = MYSQL_PORT;
uint client_flag = 0;

Change those two rows to:

unsigned int port = MYSQL_PORT;
unsigned int client_flag = 0;

Step 3 – Fix the mysql_config location (not always necessary)

You might need to open up the site.cfg file in your mysql-python directory and change the path to your mysql_config.

#mysql_config = /path to your mysql_config

Step 4 – Open up your terminal

You will need to create a symbolic link between /usr/local/mysql/lib and /usr/local/mysql/lib/mysql. Open up your terminal and do the following.

$ sudo ln -s /usr/local/mysql/lib /usr/local/mysql/lib/mysql

Step 4 – Rebuild and install

All done! You should be able to build and install mysql-python now. With your terminal in the mysql-python directory you should do the following.

$ sudo python setup.py build
$ sudo python setup.py install