old_contents: from setuptools import setup
  
  setup(
      name='pwlf',
      version='1.1.6',
      author='Charles Jekel',
      author_email='cjekel@gmail.com',
      packages=['pwlf'],
      url='https://github.com/cjekel/piecewise_linear_fit_py',
      license='MIT License',
      description='fit piecewise linear functions to data',
      long_description=open('README.rst').read(),
      platforms=['any'],
      install_requires=[
          "numpy >= 1.14.0",
          "scipy >= 0.19.0",
          "pyDOE >= 0.3.8",
      ],
      extras_require={
          'PiecewiseLinFitTF':  ["tensorflow < 2.0.0"]
      }
  )
  
new_contents: from setuptools import setup
  
  setup(
      name='pwlf',
      version='1.1.6',
      author='Charles Jekel',
      author_email='cjekel@gmail.com',
      packages=['pwlf'],
      url='https://github.com/cjekel/piecewise_linear_fit_py',
      license='MIT License',
      description='fit piecewise linear functions to data',
      long_description=open('README.rst').read(),
      platforms=['any'],
      install_requires=[
          "numpy >= 1.14.0",
          "scipy >= 0.19.0",
          "pyDOE >= 0.3.8",
          "setuptools >= 38.6.0",
      ],
      extras_require={
          'PiecewiseLinFitTF':  ["tensorflow < 2.0.0"]
      }
  )
  
subject: add setuptools as a requirement