old_contents: # -*- coding: utf-8 -*-
  
  import os
  import re
  from setuptools import setup, find_packages
  
  here = os.path.dirname(__file__)
  with open(os.path.join(here, 'src', '{{cookiecutter.project_slug}}', '__init__.py')) as v_file:
      package_version = re.compile(r".*__version__ = '(.*?)'", re.S).match(v_file.read()).group(1)
  
  
  def read(fname):
      return open(os.path.join(here, fname)).read()
  
  requirements = []
  
  test_requires = [
      'pytest',
      'pytest-cov'
  ]
  
  extras_require = {
      'docs': ['sphinx'],
      'tests': test_requires
  }
  
  setup(
      name='{{cookiecutter.project_slug}}',
      version=package_version,
      description='It\'s a python package template only',
      long_description=(
          read('README.rst') + '\n\n' + read('CHANGES.rst')
      ),
      keywords='python template',
      author='{{cookiecutter.author}}',
      author_email='{{cookiecutter.email}}',
      url='https://github.com/{{cookiecutter.github_username}}/{{cookiecutter.project_slug}}',
      license="MIT License",
      classifiers=[
          'Development Status :: 5 - Production/Stable',
          'Environment :: Web Environment',
          'Intended Audience :: Developers',
          'License :: OSI Approved :: MIT License',
          'Natural Language :: English',
          'Operating System :: OS Independent',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Programming Language :: Python :: 3',
          'Topic :: Software Development :: Libraries :: Python Modules',
      ],
      package_dir = {'': 'src'},
      packages=find_packages('src'),
      install_requires=requirements,
      tests_require=test_requires,
      test_suite='tests',
      include_package_data=True,
      zip_safe=False,
      extras_require=extras_require,
  )
  
new_contents: # -*- coding: utf-8 -*-
  
  import os
  import re
  from setuptools import setup, find_packages
  
  here = os.path.dirname(__file__)
  with open(os.path.join(here, 'src', '{{cookiecutter.project_slug}}', '__init__.py')) as v_file:
      package_version = re.compile(r".*__version__ = '(.*?)'", re.S).match(v_file.read()).group(1)
  
  
  def read(fname):
      """
      Read given file's content.
  
      :param str fname: file name
      :returns: file contents
      :rtype: str
      """
      return open(os.path.join(here, fname)).read()
  
  requirements = []
  
  test_requires = [
      'pytest',
      'pytest-cov'
  ]
  
  extras_require = {
      'docs': ['sphinx'],
      'tests': test_requires
  }
  
  setup(
      name='{{cookiecutter.project_slug}}',
      version=package_version,
      description='It\'s a python package template only',
      long_description=(
          read('README.rst') + '\n\n' + read('CHANGES.rst')
      ),
      keywords='python template',
      author='{{cookiecutter.author}}',
      author_email='{{cookiecutter.email}}',
      url='https://github.com/{{cookiecutter.github_username}}/{{cookiecutter.project_slug}}',
      license="MIT License",
      classifiers=[
          'Development Status :: 5 - Production/Stable',
          'Environment :: Web Environment',
          'Intended Audience :: Developers',
          'License :: OSI Approved :: MIT License',
          'Natural Language :: English',
          'Operating System :: OS Independent',
          'Programming Language :: Python',
          'Programming Language :: Python :: 2.7',
          'Programming Language :: Python :: 3',
          'Topic :: Software Development :: Libraries :: Python Modules',
      ],
      package_dir = {'': 'src'},
      packages=find_packages('src'),
      install_requires=requirements,
      tests_require=test_requires,
      test_suite='tests',
      include_package_data=True,
      zip_safe=False,
      extras_require=extras_require,
  )
  
subject: document setup.py's internal functions