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We need to add a check in the travis builds of our django modules that ensures migrations reflect all the latest changes in our django models because we often forget.

The check to perform is the following: https://github.com/openwisp/django-netjsonconfig/blob/master/.travis.yml#L37 It needs to be added after the tests are finished running.

Choose one of our django based repositories (including netjson/django-netjsongraph, but excluding django-netjsonconfig because this issue has been already solved there) and please perform the following steps in the right order:

• look if this issue has been opened/closed there yet (look at open and closed issues)
• if not, please open an issue
• submit a PR - remember to use the automatic issue closing feature of github to close the issue you created in the first step
• if the build fails because of the new check, good! It means it works, let it fail the first time, this is not a problem, we need to be sure the check works
• if the build has failed, create the migrations and include them in the PR so the build will be fixed