old_contents: #!/usr/bin/env python
  import codecs
  from setuptools import setup, find_packages
  
  
  def read_files(*filenames):
      """
      Output the contents of one or more files to a single concatenated string.
      """
      output = []
      for filename in filenames:
          f = codecs.open(filename, encoding='utf-8')
          try:
              output.append(f.read())
          finally:
              f.close()
      return '\n\n'.join(output)
  
  
  setup(
      name='django-countries',
      version='5.1',
      description='Provides a country field for Django models.',
      long_description=read_files('README.rst', 'CHANGES.rst'),
      author='Chris Beaven',
      author_email='smileychris@gmail.com',
      url='https://github.com/SmileyChris/django-countries/',
      packages=find_packages(),
      zip_safe=False,
      include_package_data=True,
      classifiers=[
          'Development Status :: 5 - Production/Stable',
          'Environment :: Web Environment',
          'Intended Audience :: Developers',
          'License :: OSI Approved :: MIT License',
          'Operating System :: OS Independent',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Programming Language :: Python :: 3.3',
          'Programming Language :: Python :: 3.4',
          'Programming Language :: Python :: 3.5',
          'Programming Language :: Python :: 3.6',
          'Framework :: Django',
      ],
  )
  
new_contents: #!/usr/bin/env python
  import codecs
  from setuptools import setup, find_packages
  
  
  def read_files(*filenames):
      """
      Output the contents of one or more files to a single concatenated string.
      """
      output = []
      for filename in filenames:
          f = codecs.open(filename, encoding='utf-8')
          try:
              output.append(f.read())
          finally:
              f.close()
      return '\n\n'.join(output)
  
  
  setup(
      name='django-countries',
      version='5.1',
      description='Provides a country field for Django models.',
      long_description=read_files('README.rst', 'CHANGES.rst'),
      author='Chris Beaven',
      author_email='smileychris@gmail.com',
      url='https://github.com/SmileyChris/django-countries/',
      packages=find_packages(),
      zip_safe=False,
      include_package_data=True,
      extras_require={
          'dev': ['transifex-client', 'zest.releaser[recommended]'],
      },
      classifiers=[
          'Development Status :: 5 - Production/Stable',
          'Environment :: Web Environment',
          'Intended Audience :: Developers',
          'License :: OSI Approved :: MIT License',
          'Operating System :: OS Independent',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Programming Language :: Python :: 3.3',
          'Programming Language :: Python :: 3.4',
          'Programming Language :: Python :: 3.5',
          'Programming Language :: Python :: 3.6',
          'Framework :: Django',
      ],
  )
  
subject: Add optional dev packages to setup.py