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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 wsgi_simple_responder( result: Union[str, bytes], handler: Callable[[Union[str, bytes]], WSGI_TUPLE_TYPE], start_response: TYPE_WSGI_START_RESPONSE, status: str = '200 OK', extraheaders: TYPE_WSGI_RESPONSE_HEADERS = None) \ -> TYPE_WSGI_APP_RESULT: """ Simple WSGI app. Args: result: the data to be processed by ``handler`` handler: a function returning a ``(contenttype, extraheaders, data)`` tuple, e.g. ``text_result``, ``html_result`` start_response: standard WSGI ``start_response`` function status: status code (default ``"200 OK"``) extraheaders: optional extra HTTP headers Returns: WSGI application result """

    extraheaders = extraheaders or []
    (contenttype, extraheaders2, output) = handler(result)
    response_headers = [('Content-Type', contenttype),
                        ('Content-Length', str(len(output)))]
    response_headers.extend(extraheaders)
    if extraheaders2 is not None:
        response_headers.extend(extraheaders2)
    # noinspection PyArgumentList
    start_response(status, response_headers)
    return [output]