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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 download(url):
 """Uses requests to download an URL, maybe from a file"""

    session = requests.Session()
    session.mount('file://', FileAdapter())

    try:
        res = session.get(url)
    except requests.exceptions.ConnectionError as e:
        raise e

    res.raise_for_status()

    return res