class_docstr: Additive combination of two optimizers (specification key: `plus`).
  
  Args:
      optimizer1 (specification): First optimizer configuration
          (<span style="color:#C00000"><b>required</b></span>).
      optimizer2 (specification): Second optimizer configuration
          (<span style="color:#C00000"><b>required</b></span>).
      name (string): (<span style="color:#0000C0"><b>internal use</b></span>).
      arguments_spec (specification): <span style="color:#0000C0"><b>internal use</b></span>.
code: def step(self, *, arguments, **kwargs):
      deltas1 = self.optimizer1.step(arguments=arguments, **kwargs)
  
      with tf.control_dependencies(control_inputs=deltas1):
          deltas2 = self.optimizer2.step(arguments=arguments, **kwargs)
  
      with tf.control_dependencies(control_inputs=deltas2):
          return [
              delta1 + delta2
              for delta1, delta2 in zip(deltas1, deltas2)
          ]
  
imports: import tensorflow
  import tensorforce.core
  from tensorforce.core import tf_function
  from tensorforce.core.optimizers import Optimizer
label_desc: Use image node_id 2 for calling the Plus obj's underlying member method code with example usage: obj.step() and returns: unknown