code: def __call__(self, obs, action, reuse=False):
      with tf.variable_scope(self.name, reuse=tf.AUTO_REUSE):
          x = tf.concat(
              [obs, action], axis=-1
          )  # this assumes observation and action can be concatenated
          x = self.network_builder(x)
          x = tf.layers.dense(
              x,
              1,
              kernel_initializer=tf.random_uniform_initializer(
                  minval=-3e-3, maxval=3e-3
              ),
              name="output",
          )
      return x
  
file_path: baselines/baselines/ddpg/models.py
imports: import tensorflow
  from baselines.common.models import get_network_builder
label_desc: Use image node_id 2 for calling the Critic obj's underlying member method code with example usage: obj.__call__(obs, action, reuse) and returns: x