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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 resolve_url(url, desktop_user_agent=None, mobile_user_agent=None):
 """ Url Resolver Given a url a list of resolved urls is returned for desktop and mobile user agents """

    if not desktop_user_agent:
        desktop_user_agent = DESKTOP_USER_AGENT
    if not mobile_user_agent:
        mobile_user_agent = MOBILE_USER_AGENT

    input_urls = set()

    parsed = urlparse(url_with_protocol(url))
    netloc = parsed.netloc

    if netloc.startswith('www.'):
        netloc = netloc[4:]

    input_urls.add('http://%s%s' % (netloc, parsed.path if parsed.path else '/'))
    input_urls.add('http://www.%s%s' % (netloc, parsed.path if parsed.path else '/'))

    resolved_urls = set()

    for input_url in input_urls:
        desktop_request = requests.get(input_url, headers={'User-Agent': desktop_user_agent})
        resolved_urls.add(desktop_request.url)
        mobile_request = requests.get(input_url, headers={'User-Agent': mobile_user_agent})
        resolved_urls.add(mobile_request.url)

    return list(resolved_urls)