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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_files(files):
    '''download an array of files'''
    for (url, file) in files:
        print("Downloading %s as %s" % (url, file))
        data = download_url(url)
        if data is None:
            continue
        try:
            open(file, mode='wb').write(data)
        except Exception as e:
            print("Failed to save to %s : %s" % (file, e))