code: def flatten_dict(nested, sep="/"):
      """Flatten dictionary and concatenate nested keys with separator."""
  
      def rec(nest, prefix, into):
          for k, v in nest.items():
              if sep in k:
                  raise ValueError(
                      f"separator '{sep}' not allowed to be in key '{k}'"
                  )
              if isinstance(v, Mapping):
                  rec(v, prefix + k + sep, into)
              else:
                  into[prefix + k] = v
  
      flat: Dict[str, Any] = {}
      rec(nested, "", flat)
      return flat
  
imports: import math
  import time
  import warnings
  from collections.abc import Mapping
  from typing import Any, Dict, List, Optional, Union
  import numpy
  import torch
  import torch.nn.functional
  from datasets import Dataset
  from huggingface_hub import PyTorchModelHubMixin
  from torch.cuda.amp import autocast
  from torch.nn.utils.rnn import pad_sequence
  from torch.utils.data import DataLoader
  from transformers import DataCollatorForLanguageModeling, PreTrainedTokenizer, PreTrainedTokenizerFast
  from llm_studio.src.utils.modeling_utils import unwrap_model
label_desc: Use image node_id 1 for calling a global function with example usage: flatten_dict(nested, sep) and returns: flat