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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 _verify_dict(self, conf):
 """ Check that the configuration contains all necessary keys. :type conf: dict :rtype: None :raise SATOSAConfigurationError: if the configuration is incorrect :param conf: config to verify :return: None """

        if not conf:
            raise SATOSAConfigurationError("Missing configuration or unknown format")

        for key in SATOSAConfig.mandatory_dict_keys:
            if key not in conf:
                raise SATOSAConfigurationError("Missing key '%s' in config" % key)

        for key in SATOSAConfig.sensitive_dict_keys:
            if key not in conf and "SATOSA_{key}".format(key=key) not in os.environ:
                raise SATOSAConfigurationError("Missing key '%s' from config and ENVIRONMENT" % key)