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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 _httpResponseToMessage(response, server_url):
 """Adapt a POST response to a Message. @type response: L{openid.fetchers.HTTPResponse} @param response: Result of a POST to an OpenID endpoint. @rtype: L{openid.message.Message} @raises openid.fetchers.HTTPFetchingError: if the server returned a status of other than 200 or 400. @raises ServerError: if the server returned an OpenID error. """

    # Should this function be named Message.fromHTTPResponse instead?
    response_message = Message.fromKVForm(response.body)
    if response.status == 400:
        raise ServerError.fromMessage(response_message)

    elif response.status not in (200, 206):
        fmt = 'bad status code from server %s: %s'
        error_message = fmt % (server_url, response.status)
        raise fetchers.HTTPFetchingError(error_message)

    return response_message