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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 http_keepalive (headers):
 """ Get HTTP keepalive value, either from the Keep-Alive header or a default value. @param headers: HTTP headers @type headers: dict @return: keepalive in seconds @rtype: int """

    keepalive = headers.get("Keep-Alive")
    if keepalive is not None:
        try:
            keepalive = int(keepalive[8:].strip())
        except (ValueError, OverflowError):
            keepalive = DEFAULT_KEEPALIVE
    else:
        keepalive = DEFAULT_KEEPALIVE
    return keepalive