code: def value(self, obs):
      obs = torch.FloatTensor(obs).to(self.device)
      value = self.alg.value(obs)
      value = value.cpu().detach().numpy()
      return value
  
file_path: PARL/benchmark/torch/ppo/agent.py
imports: import parl
  import torch
  import numpy
  from parl.utils.scheduler import LinearDecayScheduler
label_desc: Use image node_id 4 for calling the PPOAgent obj's underlying member method code with example usage: obj.value(obs) and returns: value