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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 validate_request_timestamp(req_body, max_diff=150):
 """Ensure the request's timestamp doesn't fall outside of the app's specified tolerance. Returns True if this request is valid, False otherwise. :param req_body: JSON object parsed out of the raw POST data of a request. :param max_diff: Maximum allowable difference in seconds between request timestamp and system clock. Amazon requires <= 150 seconds for published skills. """


    time_str = req_body.get('request', {}).get('timestamp')

    if not time_str:
        log.error('timestamp not present %s', req_body)
        return False

    req_ts = datetime.strptime(time_str, "%Y-%m-%dT%H:%M:%SZ")
    diff = (datetime.utcnow() - req_ts).total_seconds()

    if abs(diff) > max_diff:
        log.error('timestamp difference too high: %d sec', diff)
        return False

    return True