docstr: Initialize one model and one optimizer with an optional learning rate scheduler.
  
  This calls :func:`deepspeed.initialize` internally.
docstr_tok: ["Initialize","one","model","and","one","optimizer","with","an","optional","learning","rate","scheduler",".","This","calls",":","func",":","`","deepspeed.initialize","`","internally","."]
code: def _initialize_engine(
      self,
      model: Module,
      optimizer: Optional[Optimizer] = None,
  ) -> Tuple["DeepSpeedEngine", Optimizer]:
      """Initialize one model and one optimizer with an optional learning rate scheduler.
  
      This calls :func:`deepspeed.initialize` internally.
  
      """
      import deepspeed
  
      model_parameters = filter(
          lambda p: p.requires_grad, model.parameters()
      )
      (
          deepspeed_engine,
          deepspeed_optimizer,
          _,
          _,
      ) = deepspeed.initialize(
          args=argparse.Namespace(device_rank=self.root_device.index),
          config=self.config,
          model=model,
          model_parameters=model_parameters,
          optimizer=optimizer,
          dist_init_required=False,
      )
      return deepspeed_engine, deepspeed_optimizer
  
imports: import argparse
  import json
  import logging
  import os
  import platform
  from contextlib import ExitStack
  from itertools import chain
  from pathlib import Path
  from typing import TYPE_CHECKING, Any, Callable, ContextManager, Dict, List, Mapping, Optional, Tuple, Union
  import torch
  from lightning_utilities.core.imports import RequirementCache
  from torch.nn import Module
  from torch.optim import Optimizer
  from typing_extensions import override
  from lightning.fabric.accelerators import Accelerator, CUDAAccelerator
  from lightning.fabric.plugins.environments.cluster_environment import ClusterEnvironment
  from lightning.fabric.plugins.precision import Precision
  from lightning.fabric.strategies.ddp import DDPStrategy
  from lightning.fabric.strategies.registry import _StrategyRegistry
  from lightning.fabric.strategies.strategy import _Sharded
  from lightning.fabric.utilities.distributed import log
  from lightning.fabric.utilities.load import _move_state_into
  from lightning.fabric.utilities.rank_zero import rank_zero_info, rank_zero_warn
  from lightning.fabric.utilities.seed import reset_seed
  from lightning.fabric.utilities.types import _PATH
label_desc: Use image node_id 15 for calling the DeepSpeedStrategy obj's underlying member method code with example usage: obj._initialize_engine(model, optimizer) and returns: deepspeed_engine,  deepspeed_optimizer