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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 wrap_json_params(func):
 """ A middleware that parses the body of json requests and add it to the request under the `params` key. """


    @functools.wraps(func)
    def wrapper(request, *args, **kwargs):
        ctype, pdict = parse_header(request.headers.get('Content-Type', ''))
        if ctype == "application/json":
            request.params = json.loads(request.body.decode("utf-8")) if request.body else None
        return func(request, *args, **kwargs)
    return wrapper