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tests/README.md

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 # PyTorch-Lightning Tests
 Most PL tests train a full MNIST model under various trainer conditions (ddp, ddp2+amp, etc...).
 This provides testing for most combinations of important settings.
+The tests expect the model to perform to a reasonable degree of testing accuracy to pass.
 
 ## Running tests
 The automatic travis tests ONLY run CPU-based tests. Although these cover most of the use cases,