setup.py

import os

from setuptools import setup, find_packages
from setuptools.extension import Extension
from Cython.Build import cythonize
from Cython.Distutils import build_ext
import numpy


extensions = [
    Extension("openpiv.process",["./openpiv/process.pyx"],include_dirs = [numpy.get_include()]),
    Extension("openpiv.lib",["./openpiv/lib.pyx"], include_dirs = [numpy.get_include()])
    ]

extensions = cythonize(extensions,include_path = [numpy.get_include()])


# read the contents of your README file
from os import path
this_directory = path.abspath(path.dirname(__file__))
#with open(path.join(this_directory, 'README.md'), encoding='utf-8') as f:
with open(path.join(this_directory, 'README.md')) as f:
    long_description = f.read()

setup(
    name = "OpenPIV",
    version ='0.21.8c',
    cmdclass = {'build_ext': build_ext},
    ext_modules = extensions,
    packages=find_packages(),
    include_package_data=True,
    setup_requires=[
        'setuptools',
        'cython>=0.29.14',
        'numpy'
    ],
    install_requires=[
        'cython>=0.29.14',
        'numpy',            
        'imageio',
        'matplotlib>=3',
        'scikit-image',
        'progressbar2',
        'scipy',
    ],
    classifiers = [
        # PyPI-specific version type. The number specified here is a magic constant
        # with no relation to this application's version numbering scheme. *sigh*
        'Development Status :: 4 - Beta',

        # Sublist of all supported Python versions.
        'Programming Language :: Python :: 3.7',
        'Programming Language :: Python :: 3.8',

        # Sublist of all supported platforms and environments.
        'Environment :: Console',
        'Environment :: MacOS X',
        'Environment :: Win32 (MS Windows)',
        'Environment :: X11 Applications',

        # Miscellaneous metadata.
        'Intended Audience :: Science/Research',
        'License :: OSI Approved :: GNU General Public License v3 (GPLv3)',
        'Natural Language :: English',
        'Operating System :: OS Independent',
        'Topic :: Scientific/Engineering',
    ],
    long_description=long_description,
    long_description_content_type='text/markdown'
)