code: def generate_pjrt_gpu_plugin_options(
      visible_devices: str = "all",
  ) -> _NameValueMapping:
      """Generates the PjRt GPU plugin options.
  
      Args:
        visible_devices: A string of visible cuda devices.
  
      Returns:
        A dictionary of plugin options.
      """
  
      options = {}
      if visible_devices != "all":
          options["visible_devices"] = [
              int(x) for x in visible_devices.split(",")
          ]
          options["platform_name"] = "cuda"
      allocator = os.getenv(
          "XLA_PYTHON_CLIENT_ALLOCATOR", "default"
      ).lower()
      memory_fraction = os.getenv("XLA_PYTHON_CLIENT_MEM_FRACTION", "")
      preallocate = os.getenv("XLA_PYTHON_CLIENT_PREALLOCATE", "")
      if allocator not in ("default", "platform", "bfc", "cuda_async"):
          raise ValueError(
              'XLA_PYTHON_CLIENT_ALLOCATOR env var must be "default", "platform", '
              '"bfc", or "cuda_async", got "%s"' % allocator
          )
      options["allocator"] = allocator
      if memory_fraction:
          options["memory_fraction"] = float(memory_fraction)
      if preallocate:
          options["preallocate"] = preallocate not in (
              "false",
              "False",
              "0",
          )
      return options
  
imports: from __future__ import annotations
  import atexit
  import contextlib
  import enum
  import gzip
  import inspect
  import logging
  import os
  import threading
  from typing import Any, List, Mapping, Optional, Sequence, Tuple, Union
  import ml_dtypes
  import numpy
  from .None import xla_extension
label_desc: Use image node_id 11 for calling a global function with example usage: generate_pjrt_gpu_plugin_options(visible_devices) and returns: options