old_contents: from setuptools import setup
  from distutils import sysconfig
  import re
  #from setuptools.dist import Distribution
  
  site_packages_path = sysconfig.get_python_lib()
  sprem = re.match(
      r'.*(lib[\\/](python\d\.\d[\\/])?site-packages)', site_packages_path, re.I)
  rel_site_packages = sprem.group(1)
  
  #class PureDistribution(Distribution):
  #    def is_pure(self):
  #        return True
      
  setup(
      name = 'coverage_pth',
      version = '0.0.1',
      description = 'Coverage PTH file to enable coverage at the virtualenv level',
      #packages = '..',
      #include_pacakage_date=True,
      data_files=[
          (rel_site_packages, ['coverage_pth.pth',]),
      ],
      install_requires=[
          'coverage',
      ],
      #distclass=PureDistribution,
      zip_safe=False,
  )
new_contents: from setuptools import setup
  from distutils import sysconfig
  import re
  #from setuptools.dist import Distribution
  
  site_packages_path = sysconfig.get_python_lib()
  try:
      sprem = re.match(
          r'.*(lib[\\/](python\d(\.\d)*[\\/])?site-packages)', site_packages_path, re.I)
      if sprem is None:
          sprem = re.match(
              r'.*(lib[\\/](python\d(\.\d)*[\\/])?dist-packages)', site_packages_path, re.I)
      rel_site_packages = sprem.group(1)
  except Exception as exc:
      print("I'm having trouble finding your site-packages directory.  Is it where you expect?")
      print("sysconfig.get_python_lib() returns '{}'".format(site_packages_path))
      print("Exception was: {}".format(exc))
      sys.exit(-1)
  
  #class PureDistribution(Distribution):
  #    def is_pure(self):
  #        return True
      
  setup(
      name = 'coverage_pth',
      version = '0.0.1',
      description = 'Coverage PTH file to enable coverage at the virtualenv level',
      #packages = '..',
      #include_pacakage_date=True,
      data_files=[
          (rel_site_packages, ['coverage_pth.pth',]),
      ],
      install_requires=[
          'coverage',
      ],
      #distclass=PureDistribution,
      zip_safe=False,
  )
  
subject: Expand regex for location of site-packages. Provide more info to user about possible failure to find site-packages