Merge pull request #75 from AfricasTalkingLtd/develop

Add document to media_types

Merge pull request #70 from AfricasTalkingLtd/develop

Merge develop

Merge pull request #66 from AfricasTalkingLtd/develop

Update error message and prevent exploding when using sandbox username

Create python-publish.yml

update version

push update to PyPI.

- fix python 3 issue

update at gateway version

Adds a tag so that we can put this on PyPI.

Adds a tag so that we can put this on PyPI.