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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 required_params(data, *r_params):
 """Check if given parameters are in the given dict, if not raise an exception. :param data: data to check :type data: dict :param r_params: required parameters :raises RequestException: if params not in data """


    if not reduce(lambda still_valid, param: still_valid and param in data,
                  r_params, True):
        raise RequestException(msg_err_missing_params(*r_params))