class_docstr: An environment for running on clusters managed by the LSF resource manager.
  
  It is expected that any execution using this ClusterEnvironment was executed
  using the Job Step Manager i.e. ``jsrun``.
  
  This plugin expects the following environment variables:
  
  ``LSB_JOBID``
    The LSF assigned job ID
  
  ``LSB_DJOB_RANKFILE``
    The OpenMPI compatible rank file for the LSF job
  
  ``JSM_NAMESPACE_LOCAL_RANK``
    The node local rank for the task. This environment variable is set by ``jsrun``
  
  ``JSM_NAMESPACE_SIZE``
    The world size for the task. This environment variable is set by ``jsrun``
  
  ``JSM_NAMESPACE_RANK``
    The global rank for the task. This environment variable is set by ``jsrun``
docstr: A helper method for getting the node rank.
  
  The node rank is determined by the position of the current node in the list of hosts used in the job. This is
  calculated by reading all hosts from ``LSB_DJOB_RANKFILE`` and finding this node's hostname in the list.
docstr_tok: ["A","helper","method","for","getting","the","node","rank",".","The","node","rank","is","determined","by","the","position","of","the","current","node","in","the","list","of","hosts","used","in","the","job",".","This","is","calculated","by","reading","all","hosts","from","``","LSB_DJOB_RANKFILE","``","and","finding","this","node","'s","hostname","in","the","list","."]
code: def _get_node_rank(self) -> int:
      """A helper method for getting the node rank.
  
      The node rank is determined by the position of the current node in the list of hosts used in the job. This is
      calculated by reading all hosts from ``LSB_DJOB_RANKFILE`` and finding this node's hostname in the list.
  
      """
      hosts = self._read_hosts()
      count: Dict[str, int] = {}
      for host in hosts:
          if host not in count:
              count[host] = len(count)
      return count[socket.gethostname()]
  
imports: import logging
  import os
  import socket
  from typing import Dict, List
  from typing_extensions import override
  from lightning.fabric.plugins.environments.cluster_environment import ClusterEnvironment
  from lightning.fabric.utilities.cloud_io import get_filesystem
label_desc: Use image node_id 13 for calling the LSFEnvironment obj's underlying member method code with example usage: obj._get_node_rank() and returns: count