old_contents: from distutils.core import setup
  from distutils.extension import Extension
  from Cython.Build import cythonize
  
  setup(
      name='cygroonga',
      version='0.1.0',
      ext_modules=cythonize([
          Extension("cygroonga", ["cygroonga.pyx"],
              libraries=["groonga"])
      ]),
      install_requires=[
          'cython',
      ],
  )
  
new_contents: from distutils.core import setup
  from distutils.extension import Extension
  from Cython.Build import cythonize
  
  setup(
      name='cygroonga',
      version='0.1.0',
      ext_modules=cythonize([
          Extension("cygroonga", ["cygroonga.pyx"],
              libraries=["groonga"])
      ]),
      install_requires=[
          'Cython',
      ],
  )
  
subject: Change cython to Cython in install_requires