code: def _get_slurm_var(name):
      """Gets the SLURM variable from the environment.
  
      Args:
        name: Name of the step variable
  
      Returns:
        SLURM_<name> from os.environ
      Raises:
        RuntimeError if variable is not found
      """
      name = "SLURM_" + name
      try:
          return os.environ[name]
      except KeyError:
          raise RuntimeError(
              "%s not found in environment. "
              "Not running inside a SLURM step?" % name
          )
  
imports: import os
  import re
  import subprocess
  from tensorflow.python.distribute.cluster_resolver.cluster_resolver import ClusterResolver
  from tensorflow.python.distribute.cluster_resolver.cluster_resolver import format_master_url
  from tensorflow.python.training.server_lib import ClusterSpec
  from tensorflow.python.util.tf_export import tf_export
label_desc: Use image node_id 3 for calling a global function with example usage: _get_slurm_var(name) and returns: os