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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_proxy_line(line):
 """ Parse proxy details from the raw text line. The text line could be in one of the following formats: * host:port * host:port:username:password """


    line = line.strip()
    match = RE_SIMPLE_PROXY.search(line)
    if match:
        return match.group(1), match.group(2), None, None

    match = RE_AUTH_PROXY.search(line)
    if match:
        host, port, user, pwd = match.groups()
        return host, port, user, pwd

    raise InvalidProxyLine('Invalid proxy line: %s' % line)