message: Add Python 3.7 to classifiers
  Python 3.7 compatibility seems fixed in 1.13, see
  eg. tensorflow/tensorflow#20517 and tensorflow/tensorflow#17022.
diff: @@ -284,6 +284,7 @@ setup(
  'Programming Language :: Python :: 3.4',
  'Programming Language :: Python :: 3.5',
  'Programming Language :: Python :: 3.6',
  + 'Programming Language :: Python :: 3.7',
  'Topic :: Scientific/Engineering',
  'Topic :: Scientific/Engineering :: Mathematics',
  'Topic :: Scientific/Engineering :: Artificial Intelligence',
  