          'Programming Language :: Python :: 3.6',
          'Programming Language :: Python :: 3.7',
          'Programming Language :: Python :: 3.8',
          'Programming Language :: Python :: 3 :: Only',
          'Topic :: Internet :: WWW/HTTP',
      ],
      project_urls={
 
</s> remove         django31: Django>=3.1a1,<3.2
 </s> add         django31: Django>=3.1,<3.2 </s> remove        {py36,py37,py38}-django31,
       {py36,py37,py38}-djangomaster,
 </s> add        {py36,py37,py38,py39}-django31,
       {py36,py37,py38,py39}-djangomaster,
        'Programming Language :: Python :: 3.9',
          'Programming Language :: Python :: 3.6',
          'Programming Language :: Python :: 3.7',
          'Programming Language :: Python :: 3.8',
        'Programming Language :: Python :: 3.9',
          'Programming Language :: Python :: 3 :: Only',
          'Topic :: Internet :: WWW/HTTP',
      ],
      project_urls={
keep keep add keep keep keep keep
 Run tests against Python 3.9 (#7517)

3.9.0 final is expected on Monday, 2020-10-05
See https://www.python.org/dev/peps/pep-0596/#schedule

Also mention Django 3.1 compat where missing. 
setup.py