* Test for start failure.
* Handling the dictionary as shard key.
* Added integration test and fixed style
* Revert extra test
* Fix style
* Fix style
* Refactoring
* Fix build
* style fix
This PR formats all the `*.py` files found under the `tests/integration`
folder. It also reorders the imports and cleans up a bunch of unused
imports.
The formatting also takes care of other things like wrapping lines and
fixing spaces and indents such that the tests look more readable.