How do gym.make go to envs/mujoco/ant.py or half_cheetah.py

[dragen1860]

Dear author:
I have a small question when trying to understand your code.
I saw you make env by call:

def make_env(env_name):
	"""
	return a function
	:param env_name:
	:return:
	"""
	def _make_env():
		return gym.make(env_name)

	return _make_env

However, you dont call ant.py or half_cheetah.py explicitly. So I wonder How do the gym know you have implemented this class HalfCheetahDirEnv and HalfCheetahVelEnv etc?

[tristandeleu]

In gym you can register custom environments so that you can call them with gym.make. The registrations are done here.