code: def forward(self, obs):
      x = F.relu(self.l1(obs))
      x = F.relu(self.l2(x))
      mean = F.tanh(self.mean_linear(x))
      log_std = torch.sigmoid(self.log_std)
      log_std = LOG_SIG_MIN + log_std * (LOG_SIG_MAX - LOG_SIG_MIN)
      log_std = torch.exp(log_std)
      scale_tril = torch.diag(log_std)
      return torch.distributions.MultivariateNormal(
          mean, scale_tril=scale_tril
      )
  
imports: from cmath import log
  import parl
  import torch
  import torch.nn
  import torch.nn.functional
label_desc: Use image node_id 2 for calling the Actor obj's underlying member method code with example usage: obj.forward(obs) and returns: torch