code: def _ensure_str(x: str) -> str:
      if not isinstance(x, str):
          raise TypeError(f"argument is not a string: {x}")
      return x
  
imports: from __future__ import annotations
  from collections.abc import Iterable, Sequence
  import inspect
  import operator
  from functools import partial
  from typing import Any, Callable
  import warnings
  import numpy
  from jax._src import core
  from jax._src import dtypes
  from jax._src.abstract_arrays import numpy_scalar_types
  from jax._src.core import ShapedArray
  from jax._src.tree_util import PyTreeDef, tree_flatten, tree_unflatten, tree_map, tree_structure, treedef_children, generate_key_paths, keystr, broadcast_prefix, prefix_errors
  from jax._src.tree_util import _replace_nones
  from jax._src import linear_util
  from jax._src.linear_util import TracingDebugInfo
  from jax._src.util import safe_map, WrapKwArgs, Hashable, HashableFunction, Unhashable
  from jax._src import traceback_util
label_desc: Use image node_id 3 for calling a global function with example usage: _ensure_str(x) and returns: x