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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 httpretty_callback(request, uri, headers):
 """httpretty request handler. converts a call intercepted by httpretty to the stack-in-a-box infrastructure :param request: request object :param uri: the uri of the request :param headers: headers for the response :returns: tuple - (int, dict, string) containing: int - the http response status code dict - the headers for the http response string - http string response """

    method = request.method
    response_headers = CaseInsensitiveDict()
    response_headers.update(headers)
    request_headers = CaseInsensitiveDict()
    request_headers.update(request.headers)
    request.headers = request_headers
    return StackInABox.call_into(method,
                                 request,
                                 uri,
                                 response_headers)