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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_cifar(directory, url):
 """Download and extract CIFAR to directory unless it is there."""

  filename = os.path.basename(url)
  path = generator_utils.maybe_download(directory, filename, url)
  tarfile.open(path, "r:gz").extractall(directory)