GDrive doesn't download the model checkpoints correctly sometimes, leading to the following error:

``` # Setup model

I get an error in the function call 'prepare_model'

UnpicklingError: invalid load key, '<'. ```

Try rerunning the download cell if you experience this - the models downloaded should be around 1.5-2GB, so if the checkpoints are 100kB in size, the download's gone wrong.