old_contents: from distutils.core import setup, Extension
  from evoMPS.version import __version__
  
  setup(name='evoMPS',
        version=__version__,
        description='Python scripts for simulating time evolution of matrix product states',
        author='Ashley Milsted',
        url='https://github.com/amilsted/evoMPS',
        license="BSD",
        classifiers=[
          'Environment :: Console',
          'Development Status :: 4 - Beta',
          'Intended Audience :: Developers',
          'Intended Audience :: Other Audience',
          'Intended Audience :: Science/Research',
          'License :: OSI Approved :: BSD License',
          'Natural Language :: English',
          'Programming Language :: Python',
          'Topic :: Scientific/Engineering',
          'Topic :: Scientific/Engineering :: Physics',
        ],      
        packages = ['evoMPS'],
        requires = ["scipy (>=0.7)"],
        )
  
new_contents: from distutils.core import setup, Extension
  from evoMPS.version import __version__
  
  from Cython.Distutils import build_ext
  
  ext_modules = [Extension("evoMPS.matmul", ["evoMPS/matmul.py"]),
                 Extension("evoMPS.tdvp_common", ["evoMPS/tdvp_common.pyx"]),
                 Extension("evoMPS.tdvp_uniform", ["evoMPS/tdvp_uniform.py"])]
  
  #for e in ext_modules:
  #    e.pyrex_directives = {"profile": True}
  
  setup(name='evoMPS',
        version=__version__,
        description='Python scripts for simulating time evolution of matrix product states',
        author='Ashley Milsted',
        url='https://github.com/amilsted/evoMPS',
        license="BSD",
        classifiers=[
          'Environment :: Console',
          'Development Status :: 4 - Beta',
          'Intended Audience :: Developers',
          'Intended Audience :: Other Audience',
          'Intended Audience :: Science/Research',
          'License :: OSI Approved :: BSD License',
          'Natural Language :: English',
          'Programming Language :: Python',
          'Topic :: Scientific/Engineering',
          'Topic :: Scientific/Engineering :: Physics',
        ],      
        packages = ['evoMPS'],
        requires = ["scipy (>=0.7)"],
        cmdclass = {"build_ext": build_ext},
        ext_modules = ext_modules
        )
  
subject: Add building of cython code to setup.py.