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README.md

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-A(n) **APPO** model trained on the **doom_deathmatch_bots** environment.
+An **APPO** model trained on the **doom_deathmatch_bots** environment.
 
 This model was trained using Sample-Factory 2.0: https://github.com/alex-petrenko/sample-factory.
 Documentation for how to use Sample-Factory can be found at https://www.samplefactory.dev/