text: #!/usr/bin/env python
  
  # Build or install Shapely distributions
  #
  # This script has two different uses.
  #
  # 1) Installing from a source distribution, whether via
  #
  #      ``python setup.py install``
  #
  #    after downloading a source distribution, or
  #
  #      ``pip install shapely``
  #
  #    on a platform for which pip cannot find a wheel. This will most
  #    often be the case for Linux, since the project is not yet
  #    publishing Linux wheels. This will never be the case on Windows and
  #    rarely the case on OS X; both are wheels-first platforms.
  #
  # 2) Building distributions (source or wheel) from a repository. This
  #    includes using Cython to generate C source for the speedups and
  #    vectorize modules from Shapely's .pyx files.
  #
  # On import, Shapely loads a GEOS shared library. GEOS is a run time
  # requirement. Additionally, the speedups and vectorized C extension
  # modules need GEOS headers and libraries to be built. Shapely versions
  # >=1.3 require GEOS >= 3.3.
  #
  # For the first use case (see 1, above), we aim to treat GEOS as if it
  # were a Python requirement listed in ``install_requires``. That is, in
  # an environment with Shapely 1.2.x and GEOS 3.2, the command ``pip
  # install shapely >=1.3 --no-use-wheel`` (whether wheels are explicitly
  # opted against or are not published for the platform) should fail with
  # a warning and advice to upgrade GEOS to >=3.3.
  #
  # In case 1, the environment's GEOS version is determined by executing
  # the geos-config script. If the GEOS version returned by that script is
  # incompatible with the Shapely source distribution or no geos-config
  # script can be found, this setup script will fail.
  #
  # For the second use case (see 2, distribution building, above), we
  # allow the requirements to be loosened. If this script finds that the
  # environment variable NO_GEOS_CHECK is set, geos-config will not be
  # executed and no attempt will be made to enforce requirements as in the
  # second case.
  #
  # For both cases, a geos-config not in the environment's $PATH may be
  # used by setting the environment variable GEOS_CONFIG to the path to
  # a geos-config script.
  #
  # NB: within this setup scripts, software versions are evaluated according
  # to https://www.python.org/dev/peps/pep-0440/.
  
  import errno
  import glob
  import itertools as it
  import logging
  import os
  import platform
  import re
  import shutil
  import subprocess
  import sys
  from setuptools import setup
  from setuptools.extension import Extension
  from setuptools.command.build_ext import build_ext as distutils_build_ext
  from distutils.errors import CCompilerError, DistutilsExecError, \
      DistutilsPlatformError
  
  from _vendor.packaging.version import Version
  
  # Get geos_version from GEOS dynamic library, which depends on
  # GEOS_LIBRARY_PATH and/or GEOS_CONFIG environment variables
  from shapely._buildcfg import geos_version_string, geos_version, \
          geos_config, get_geos_config
  
  logging.basicConfig()
  log = logging.getLogger(__file__)
  
  # python -W all setup.py ...
  if 'all' in sys.warnoptions:
      log.level = logging.DEBUG
  
  
  class GEOSConfig(object):
      """Interface to config options from the `geos-config` utility
      """
  
      def __init__(self, cmd):
          self.cmd = cmd
  
      def get(self, option):
          try:
              stdout, stderr = subprocess.Popen(
                  [self.cmd, option],
                  stdout=subprocess.PIPE, stderr=subprocess.PIPE).communicate()
          except OSError as ex:
              # e.g., [Errno 2] No such file or directory
              raise OSError("Could not find geos-config script")
          if stderr and not stdout:
              raise ValueError(stderr.strip())
          result = stdout.decode('ascii').strip()
          log.debug('%s %s: %r', self.cmd, option, result)
          return result
  
      def version(self):
          match = re.match(r'(\d+)\.(\d+)\.(\d+)', self.get('--version').strip())
          return tuple(map(int, match.groups()))
  
  # Get the version from the shapely module.
  shapely_version = None
  with open('shapely/__init__.py', 'r') as fp:
      for line in fp:
          if line.startswith("__version__"):
              shapely_version = Version(
                  line.split("=")[1].strip().strip("\"'"))
              break
  
  if not shapely_version:
      raise ValueError("Could not determine Shapely's version")
  
  # Allow GEOS_CONFIG to be bypassed in favor of CFLAGS and LDFLAGS
  # vars set by build environment.
  if os.environ.get('NO_GEOS_CONFIG'):
      geos_config = None
  else:
      geos_config = GEOSConfig(os.environ.get('GEOS_CONFIG', 'geos-config'))
  
  # Fail installation if the GEOS shared library does not meet the minimum
  # version. We ship it with Shapely for Windows, so no need to check on
  # that platform.
  geos_version = None
  if geos_config and not os.environ.get('NO_GEOS_CHECK') or sys.platform == 'win32':
      try:
          log.info(
              "Shapely >= 1.3 requires GEOS >= 3.3. "
              "Checking for GEOS version...")
          geos_version = geos_config.version()
          log.info("Found GEOS version: %s", geos_version)
          if (set(sys.argv).intersection(['install', 'build', 'build_ext']) and
                  shapely_version >= Version("1.3") and geos_version < (3, 3)):
              log.critical(
                  "Shapely >= 1.3 requires GEOS >= 3.3. "
                  "Install GEOS 3.3+ and reinstall Shapely.")
              sys.exit(1)
      except OSError as exc:
          log.warning(
              "Failed to determine system's GEOS version: %s. "
              "Installation continuing. GEOS version will be "
              "checked on import of shapely.", exc)
  
  with open('VERSION.txt', 'w') as fp:
      fp.write(str(shapely_version))
  
  with open('README.rst', 'r') as fp:
      readme = fp.read()
  
  with open('CREDITS.txt', 'r', encoding='utf-8') as fp:
      credits = fp.read()
  
  with open('CHANGES.txt', 'r') as fp:
      changes = fp.read()
  
  long_description = readme + '\n\n' + credits + '\n\n' + changes
  
  extra_reqs = {
      'test': ['pytest', 'pytest-cov'],
      'vectorized': ['numpy']}
  extra_reqs['all'] = list(it.chain.from_iterable(extra_reqs.values()))
  
  # Make a dict of setup arguments. Some items will be updated as
  # the script progresses.
  setup_args = dict(
      name                = 'Shapely',
      version             = str(shapely_version),
      description         = 'Geometric objects, predicates, and operations',
      license             = 'BSD',
      keywords            = 'geometry topology gis',
      author              = 'Sean Gillies',
      author_email        = 'sean.gillies@gmail.com',
      maintainer          = 'Sean Gillies',
      maintainer_email    = 'sean.gillies@gmail.com',
      url                 = 'https://github.com/Toblerity/Shapely',
      long_description    = long_description,
      packages            = [
          'shapely',
          'shapely.geometry',
          'shapely.algorithms',
          'shapely.examples',
          'shapely.speedups',
          'shapely.vectorized',
      ],
      classifiers         = [
          'Development Status :: 5 - Production/Stable',
          'Intended Audience :: Developers',
          'Intended Audience :: Science/Research',
          'License :: OSI Approved :: BSD License',
          'Operating System :: OS Independent',
          'Programming Language :: Python :: 3',
          'Programming Language :: Python :: 3.5',
          'Programming Language :: Python :: 3.6',
          'Programming Language :: Python :: 3.7',
          'Programming Language :: Python :: 3.8',
          'Programming Language :: Python :: 3.9',
          'Topic :: Scientific/Engineering :: GIS',
      ],
      cmdclass           = {},
      python_requires    = '>=3.5',
      extras_require     = extra_reqs,
      package_data={
          'shapely': ['shapely/_geos.pxi']},
      include_package_data=True
  )
  
  # Add DLLs for Windows.
  if sys.platform == 'win32':
      try:
          os.mkdir('shapely/DLLs')
      except OSError as ex:
          if ex.errno != errno.EEXIST:
              raise
      if '(AMD64)' in sys.version:
          for dll in glob.glob('DLLs_AMD64_VC9/*.dll'):
              shutil.copy(dll, 'shapely/DLLs')
      else:
          for dll in glob.glob('DLLs_x86_VC9/*.dll'):
              shutil.copy(dll, 'shapely/DLLs')
      setup_args['package_data']['shapely'].append('shapely/DLLs/*.dll')
  
  # Prepare build opts and args for the speedups extension module.
  include_dirs = []
  library_dirs = []
  libraries = []
  extra_link_args = []
  
  # If NO_GEOS_CONFIG is set in the environment, geos-config will not
  # be called and CFLAGS and LDFLAGS environment variables must be set
  # instead like
  #
  # CFLAGS="-I/usr/local/include" LDFLAGS="-L/usr/local/lib -lgeos_c"
  #
  # Or, equivalently:
  #
  # CFLAGS="$(geos-config --cflags)" LDFLAGS="$(geos-config --clibs)"
  
  if geos_version and geos_config:
      # Collect other options from GEOS configuration.
      for item in geos_config.get('--cflags').split():
          if item.startswith("-I"):
              include_dirs.extend(item[2:].split(":"))
      for item in geos_config.get('--clibs').split():
          if item.startswith("-L"):
              library_dirs.extend(item[2:].split(":"))
          elif item.startswith("-l"):
              libraries.append(item[2:])
          else:
              # e.g. -framework GEOS
              extra_link_args.append(item)
  
  
  # Optional compilation of speedups
  # setuptools stuff from Bob Ippolito's simplejson project
  if sys.platform == 'win32':
      # distutils.msvc9compiler can raise an IOError when failing to
      # find the compiler
      ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError,
                    IOError)
  else:
      ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError)
  
  
  class BuildFailed(Exception):
      pass
  
  
  def construct_build_ext(build_ext):
      class WrappedBuildExt(build_ext):
          # This class allows C extension building to fail.
  
          def run(self):
              try:
                  build_ext.run(self)
              except DistutilsPlatformError as x:
                  raise BuildFailed(x)
  
          def build_extension(self, ext):
              try:
                  build_ext.build_extension(self, ext)
              except ext_errors as x:
                  raise BuildFailed(x)
  
      return WrappedBuildExt
  
  if (platform.python_implementation() == 'PyPy'):
      ext_modules = []
      libraries = []
  
  
  pyx_file = "shapely/speedups/_speedups.pyx"
  c_file = "shapely/speedups/_speedups.c"
  
  force_cython = False
  # Always regenerate for sdist or absent c file
  if 'sdist' in sys.argv or not os.path.exists(c_file):
      force_cython = True
  # Also regenerate if pyx_file is outdated.
  elif os.path.exists(c_file):
      if os.path.getmtime(pyx_file) > os.path.getmtime(c_file):
          force_cython = True
  
  ext_modules = [
      Extension("shapely.speedups._speedups", ["shapely/speedups/_speedups.c"],
          include_dirs=include_dirs, library_dirs=library_dirs,
          libraries=libraries, extra_link_args=extra_link_args)]
  
  cmd_classes = setup_args.setdefault('cmdclass', {})
  
  try:
      import numpy
      from Cython.Distutils import build_ext as cython_build_ext
      from distutils.extension import Extension as DistutilsExtension
  
      if 'build_ext' in setup_args['cmdclass']:
          raise ValueError('We need to put the Cython build_ext in '
                           'cmd_classes, but it is already defined.')
      setup_args['cmdclass']['build_ext'] = cython_build_ext
  
      include_dirs.append(numpy.get_include())
      libraries.append(numpy.get_include())
  
      ext_modules.append(DistutilsExtension(
          "shapely.vectorized._vectorized",
          sources=["shapely/vectorized/_vectorized.pyx"],
          include_dirs=include_dirs,
          library_dirs=library_dirs,
          libraries=libraries,
          extra_link_args=extra_link_args,))
  
  except ImportError:
      log.info("Numpy or Cython not available, shapely.vectorized submodule "
               "not being built.")
      force_cython = False
  
  try:
      if force_cython:
          log.info("Updating C extension with Cython.")
          subprocess.check_call(["cython", "shapely/speedups/_speedups.pyx"])
  except (subprocess.CalledProcessError, OSError):
      log.warning("Could not (re)create C extension with Cython.")
      if force_cython:
          raise
  
  if not os.path.exists(c_file):
      log.warning("speedup extension not found")
  
  try:
      # try building with speedups
      existing_build_ext = setup_args['cmdclass'].\
          get('build_ext', distutils_build_ext)
      setup_args['cmdclass']['build_ext'] = \
          construct_build_ext(existing_build_ext)
      setup(ext_modules=ext_modules, **setup_args)
  except BuildFailed as ex:
      BUILD_EXT_WARNING = "The C extension could not be compiled, " \
                          "speedups are not enabled."
      log.warning(ex)
      log.warning(BUILD_EXT_WARNING)
      log.warning("Failure information, if any, is above.")
      log.warning("I'm retrying the build without the C extension now.")
  
      # Remove any previously defined build_ext command class.
      if 'build_ext' in setup_args['cmdclass']:
          del setup_args['cmdclass']['build_ext']
  
      if 'build_ext' in cmd_classes:
          del cmd_classes['build_ext']
  
      setup(**setup_args)
  
      log.warning(BUILD_EXT_WARNING)
      log.info("Plain-Python installation succeeded.")
  