old_contents: import sys
  
  if 'setuptools' in sys.modules:
      try:
          from setuptools.command.build_ext import build_ext as _build_ext
      except ImportError:
          # We may be in the process of importing setuptools, which tries
          # to import this.
          from distutils.command.build_ext import build_ext as _build_ext
  else:
      from distutils.command.build_ext import build_ext as _build_ext
  
  
  class new_build_ext(_build_ext, object):
      def finalize_options(self):
          if self.distribution.ext_modules:
              from Cython.Build.Dependencies import cythonize
              self.distribution.ext_modules[:] = cythonize(
                  self.distribution.ext_modules)
          super(build_ext, self).finalize_options()
  
  # This will become new_build_ext in the future.
  from Cython.Distutils.old_build_ext as build_ext
  
new_contents: import sys
  
  if 'setuptools' in sys.modules:
      try:
          from setuptools.command.build_ext import build_ext as _build_ext
      except ImportError:
          # We may be in the process of importing setuptools, which tries
          # to import this.
          from distutils.command.build_ext import build_ext as _build_ext
  else:
      from distutils.command.build_ext import build_ext as _build_ext
  
  
  class new_build_ext(_build_ext, object):
      def finalize_options(self):
          if self.distribution.ext_modules:
              from Cython.Build.Dependencies import cythonize
              self.distribution.ext_modules[:] = cythonize(
                  self.distribution.ext_modules)
          super(build_ext, self).finalize_options()
  
  # This will become new_build_ext in the future.
  from .old_build_ext import old_build_ext as build_ext
  
subject: Fix import typo.