in robosumo/envs/agents.py [0:0]
def _set_observation_space(self):
obs = self.get_obs()
self.obs_dim = obs.size
low = -np.inf * np.ones(self.obs_dim)
high = np.inf * np.ones(self.obs_dim)
self.observation_space = gym.spaces.Box(low, high)