[README] Tweak usage instructions.
@@ -175,14 +175,16 @@ In Python, import `compiler_gym` to use the environments:
```py
>>> import gym
->>> import compiler_gym # import the CompilerGym environments
->>> env = gym.make( # create a new environment
-... "llvm-autophase-ic-v0" # select the compiler optimization task
-... benchmark="cbench-v1/qsort" # select the program to compile
+>>> import compiler_gym # imports the CompilerGym environments
+>>> env = gym.make( # creates a new environment
+... "llvm-v0", # selects the compiler to use
+... benchmark="cbench-v1/qsort", # selects the program to compile
+... reward_space="IrInstructionCountOz", # selects the optimization target
+... observation_space="Autophase", # selects the observation space
... )
->>> env.reset() # start a new compilation session
->>> env.render() # print the IR of the program
->>> env.step(env.action_space.sample()) # apply a random optimization, update state/reward/actions
+>>> env.reset() # starts a new compilation session
+>>> env.render() # prints the IR of the program
+>>> env.step(env.action_space.sample()) # applies a random optimization, updates state/reward/actions
```
See the [documentation website](http://facebookresearch.github.io/CompilerGym/)
