code: def reduce_std(tensor, axis=None, keepdims=False):
      """
      get the standard deviation of a Tensor
  
      :param tensor: (TensorFlow Tensor) the input tensor
      :param axis: (int or [int]) the axis to itterate the std over
      :param keepdims: (bool) keep the other dimensions the same
      :return: (TensorFlow Tensor) the std of the tensor
      """
      return tf.sqrt(reduce_var(tensor, axis=axis, keepdims=keepdims))
  
imports: from functools import reduce
  import os
  import time
  from collections import deque
  import pickle
  import warnings
  import gym
  import numpy
  import tensorflow
  import tensorflow.contrib
  from mpi4py import MPI
  from stable_baselines import logger
  from stable_baselines.common import tf_util, OffPolicyRLModel, SetVerbosity, TensorboardWriter
  from stable_baselines.common.vec_env import VecEnv
  from stable_baselines.common.mpi_adam import MpiAdam
  from stable_baselines.common.buffers import ReplayBuffer
  from stable_baselines.common.math_util import unscale_action, scale_action
  from stable_baselines.common.mpi_running_mean_std import RunningMeanStd
  from stable_baselines.ddpg.policies import DDPGPolicy
label_desc: Use image node_id 3 for calling a global function with example usage: reduce_std(tensor, axis, keepdims) and returns: tf