code: def _unique_string() -> str:
      return str(uuid.uuid4()).replace("-", "")
  
imports: import copy
  import random
  import string
  import uuid
  from multiprocessing import Pool
  import numpy
  import pandas
  import pyarrow
  from pyarrow import parquet
  import cudf
  from cudf.utils.dtypes import np_to_pa_dtype
label_desc: Use image node_id 21 for calling a global function with example usage: _unique_string() and returns: str