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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 fetch_url(url, dest, parent_to_remove_before_fetch):
 """Helper function to fetch a file from a URL."""

    logger.debug('Downloading file {} from {}', dest, url)
    try:
        shutil.rmtree(parent_to_remove_before_fetch)
    except FileNotFoundError:
        pass
    os.makedirs(parent_to_remove_before_fetch)
    # TODO(itamar): Better downloading (multi-process-multi-threaded?)
    # Consider offloading this to a "standalone app" invoked with Docker
    resp = requests.get(url, stream=True)
    with open(dest, 'wb') as fetch_file:
        for chunk in resp.iter_content(chunk_size=32 * 1024):
            fetch_file.write(chunk)