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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 url_as_file(url, ext=None):
 """ Context manager that GETs a given `url` and provides it as a local file. The file is in a closed state upon entering the context, and removed when leaving it, if still there. To give the file name a specific extension, use `ext`; the extension can optionally include a separating dot, otherwise it will be added. Parameters: url (str):
 URL to retrieve. ext (str, optional):
 Extension for the generated filename. Yields: str: The path to a temporary file with the content of the URL. Raises: requests.RequestException: Base exception of ``requests``, see its docs for more detailed ones. Example: (u'/tmp/www-api.github.com-Ba5OhD.json', [u'192.30.252.0/22']) """

    if ext:
        ext = '.' + ext.strip('.')  # normalize extension
    url_hint = 'www-{}-'.format(urlparse(url).hostname or 'any')

    content = requests.get(url).content
    with tempfile.NamedTemporaryFile(suffix=ext or '', prefix=url_hint, delete=False) as handle:
        handle.write(content)

    try:
        yield handle.name
    finally:
        if os.path.exists(handle.name):
            os.remove(handle.name)