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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 parse_url(url):
 """ Takes a URL string and returns its protocol and server """

    # Verify that the protocol makes sense.  We shouldn't guess!
    if not RE_PROTOCOL_SERVER.match(url):
        raise Exception("URL should begin with `protocol://domain`")

    protocol, server, path, _, _, _ = urlparse.urlparse(url)

    return protocol, server