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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 normalize_request(request):
 """ Given a request, normalize it to the internal Request class. """

    if isinstance(request, Request):
        return request

    for normalizer in REQUEST_NORMALIZERS:
        try:
            return normalizer(request)
        except TypeError:
            continue

    raise ValueError("Unable to normalize the provided request")