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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 main(arguments=None):
    '''Converts a given url with the specified arguments.'''

    parsed_options, arguments = get_options(arguments)

    image_url = arguments[0]
    image_url = quote(image_url)

    try:
        config = Config.load(None)
    except Exception:
        config = None

    if not parsed_options.key and not config:
        sys.stdout.write('Error: The -k or --key argument is mandatory. For more information type thumbor-url -h\n')
        return

    security_key, thumbor_params = get_thumbor_params(image_url, parsed_options, config)

    crypto = CryptoURL(key=security_key)
    url = crypto.generate(**thumbor_params)
    sys.stdout.write('URL:\n')
    sys.stdout.write('%s\n' % url)

    return url