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The major change is:
* Made all functions protected in the modules responsible for code generation.
This impacts only the users which used swagger-to as a library. This change does not affect users which use
swagger-to only as CLI.
The minor changes are:
* Rewritten go-server and py-client generation with jinja2 template engine.
The generated code is semantically equal to the previous version, but a bit more readable and easier to diff
since we enforce now the line width of 100 columns and split argument lists into multiple lines.
* swagger-to-py-client includes a response description in the docstring of the request function.
* Refactored tests into a hierarchy of test case directories
* Added test cases with files, empty objects and objects with optional fields to swagger-to-py-client and go-server.