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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 json(cls, status_code, process):
 """Callback to validate and extract a JSON object. The returned callback checks a given response for the given status_code using :function:`response_boolean`. On success the response JSON is parsed and returned. Args: status_code(int):
 The http status code to consider a success Returns: A function that given a response returns the JSON object in the given response. Raises a :class:`HeliumError` if the response code does not match. """

        def func(response):
            ret = None
            if cls.boolean(status_code)(response):
                ret = response.json() or {}
            return process(ret)
        return func