#!/usr/bin/python

import sys
print "Current Python Version::  ", (sys.version)

import subprocess
from subprocess import check_output    # <<<<<<<< error here!

output = subprocess.check_output(['ls', '-1', '|', 'grep', 'somefile.txt'])
print 'Have %d bytes in output' % len(output)
print output

[Linux]$ python myCode.py
Current Python Version::   2.4.3 (#1, Apr 14 2011, 20:41:59)
[GCC 4.1.2 20080704 (Red Hat 4.1.2-50)]
Traceback (most recent call last):
  File "myCode.py", line 7, in ?
    from subprocess import check_output
ImportError: cannot import name check_output
[Linux]$