code: def download_file(url, cache="~/.elegy/downloads", sha256=None):
      if cache.startswith("~/"):
          cache = os.path.join(os.path.expanduser("~"), cache[2:])
      cachefilename = os.path.basename(url)
      cachefilename = cachefilename[: cachefilename.find("?")]
      cachefilename = os.path.join(cache, cachefilename)
  
      if not os.path.exists(cachefilename):
          print(f"Downloading {url}")
          filename, _ = urllib.request.urlretrieve(url)
          if sha256 is not None:
              filehash = hashlib.sha256(
                  open(filename, "rb").read()
              ).hexdigest()
              if sha256 != filehash:
                  raise RuntimeError(
                      "Downloaded file has an incorrect hash"
                  )
          os.makedirs(os.path.dirname(cachefilename), exist_ok=True)
          shutil.move(filename, cachefilename)
  
      return cachefilename
  
imports: import enum
  import functools
  import hashlib
  import inspect
  import io
  import os
  import re
  import shutil
  import sys
  import typing
  import urllib
  from functools import total_ordering
  import jax
  import jax.numpy
  import jax.tree_util
  import numpy
  import treex
  from elegy import types
label_desc: Use image node_id 17 for calling a global function with example usage: download_file(url, cache, sha256) and returns: cachefilename