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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 _check_result_dict_for_needed_keys(self, results_dict):
 """ Ensure that `results_dict` has the needed keys to store all the estimation results. Raise a helpful ValueError otherwise. """

        missing_cols = [x for x in needed_result_keys if x not in results_dict]
        if missing_cols != []:
            msg = "The following keys are missing from results_dict\n{}"
            raise ValueError(msg.format(missing_cols))
        return None