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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_post(blink, url, is_retry=False):
 """ Perform an http post request. :param url: URL to perfom post request. :param is_retry: Is this part of a re-auth attempt? """

    if blink.auth_header is None:
        raise BlinkException(ERROR.AUTH_TOKEN)
    _LOGGER.debug("Making POST request to %s", url)
    return http_req(blink, url=url, headers=blink.auth_header,
                    reqtype='post', is_retry=is_retry)