        - { python: "3.6", env: DJANGO=master }
        - { python: "3.6", env: DJANGO=1.11 }
        - { python: "3.6", env: DJANGO=2.0 }
        - { python: "3.6", env: DJANGO=2.1 }
        - { python: "3.6", env: TOXENV=base }
        - { python: "2.7", env: TOXENV=lint }
        - { python: "2.7", env: TOXENV=docs }
  
        - python: "3.6"
          env: TOXENV=dist
 
</s> remove       - env: DJANGO=2.1
 </s> add  </s> remove        {py34,py35,py36}-django20,
       {py35,py36}-django21
       {py35,py36}-djangomaster,
 </s> add        {py34,py35,py36,py37}-django20,
       {py35,py36,py37}-django21
       {py35,py36,py37}-djangomaster,
      - { python: "3.7", env: DJANGO=2.0, dist: xenial, sudo: true }
      - { python: "3.7", env: DJANGO=2.1, dist: xenial, sudo: true }
      - { python: "3.7", env: DJANGO=master, dist: xenial, sudo: true }

        - { python: "3.6", env: DJANGO=master }
        - { python: "3.6", env: DJANGO=1.11 }
        - { python: "3.6", env: DJANGO=2.0 }
        - { python: "3.6", env: DJANGO=2.1 }
      - { python: "3.7", env: DJANGO=2.0, dist: xenial, sudo: true }
      - { python: "3.7", env: DJANGO=2.1, dist: xenial, sudo: true }
      - { python: "3.7", env: DJANGO=master, dist: xenial, sudo: true }

        - { python: "3.6", env: TOXENV=base }
        - { python: "2.7", env: TOXENV=lint }
        - { python: "2.7", env: TOXENV=docs }
  
        - python: "3.6"
          env: TOXENV=dist
keep keep keep add keep keep keep keep keep keep
 Add Python 3.7 support (#6141) 
.travis.yml