old_contents: 
  # try using distribute or setuptools or distutils.
  try:
      import distribute_setup
      distribute_setup.use_setuptools()
  except:
      pass
  
  try:
      from setuptools import setup
  except ImportError:
      from distutils.core import setup
  
  
  import os
  import sys
  
  # parse version from package/module without importing or evaluating the code
  with open('rsd/rsd.py') as fh:
      for line in fh:
          m = re.search(r"^__version__ = '(?P<version>[^']+)'$", line)
          if m:
              version = m.group('version')
              break
  
  if sys.version_info <= (2, 6):
      sys.stderr.write("ERROR: rsd requires Python Version 2.7 or above...exiting.\n")
      sys.exit(1)
  
  setup(
      name = "reciprocal_smallest_distance",
      version = version,
      author = "Todd F. DeLuca, Dennis P. Wall",
      author_email = "todd_deluca@hms.harvard.edu",
      description = "Reciprocal Smallest Distance (RSD) finds pairwise orthologous genes using global sequence alignment and maximum likelihood evolutionary distance estimates.",
      license = "MIT",
      keywords = "genome ortholog algorithm",
      platforms = "Posix; MacOS X",
      url = "https://github.com/todddeluca/reciprocal_smallest_distance",   # project home page, if any
      download_url = "https://github.com/todddeluca/reciprocal_smallest_distance/downloads",
      scripts = ['bin/rsd_search', 'bin/rsd_format', 'bin/rsd_blast'],
      packages = ['rsd'],
      install_requires = ['tfd>=0.2.1'],
      package_data = {
          'rsd': ['*.ctl', '*.dat'],
          },
      test_suite='tests.test_search.TestSearch',
      classifiers = [
          'Development Status :: 5 - Production/Stable',
          'Environment :: Console',
          'Intended Audience :: Science/Research',
          'License :: OSI Approved :: MIT License',
          'Operating System :: MacOS :: MacOS X',
          'Operating System :: POSIX :: Linux',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Topic :: Scientific/Engineering :: Bio-Informatics',
          ],
      )
  
new_contents: 
  # try using distribute or setuptools or distutils.
  try:
      import distribute_setup
      distribute_setup.use_setuptools()
  except:
      pass
  
  try:
      from setuptools import setup
  except ImportError:
      from distutils.core import setup
  
  
  import sys
  import re
  
  # parse version from package/module without importing or evaluating the code
  with open('rsd/rsd.py') as fh:
      for line in fh:
          m = re.search(r"^__version__ = '(?P<version>[^']+)'$", line)
          if m:
              version = m.group('version')
              break
  
  if sys.version_info <= (2, 6):
      sys.stderr.write("ERROR: rsd requires Python Version 2.7 or above...exiting.\n")
      sys.exit(1)
  
  setup(
      name = "reciprocal_smallest_distance",
      version = version,
      author = "Todd F. DeLuca, Dennis P. Wall",
      author_email = "todd_deluca@hms.harvard.edu",
      description = "Reciprocal Smallest Distance (RSD) finds pairwise orthologous genes using global sequence alignment and maximum likelihood evolutionary distance estimates.",
      license = "MIT",
      keywords = "genome ortholog algorithm",
      platforms = "Posix; MacOS X",
      url = "https://github.com/todddeluca/reciprocal_smallest_distance",   # project home page, if any
      download_url = "https://github.com/todddeluca/reciprocal_smallest_distance/downloads",
      scripts = ['bin/rsd_search', 'bin/rsd_format', 'bin/rsd_blast'],
      packages = ['rsd'],
      install_requires = ['tfd>=0.2.1'],
      package_data = {
          'rsd': ['*.ctl', '*.dat'],
          },
      test_suite='tests.test_search.TestSearch',
      classifiers = [
          'Development Status :: 5 - Production/Stable',
          'Environment :: Console',
          'Intended Audience :: Science/Research',
          'License :: OSI Approved :: MIT License',
          'Operating System :: MacOS :: MacOS X',
          'Operating System :: POSIX :: Linux',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Topic :: Scientific/Engineering :: Bio-Informatics',
          ],
      )
  
subject: Add missing import.