def get_relevant_policy_section(self, policy_name, group=None):
        """
        Look up the policy corresponding to the provided policy name and
        group (optional). Log any issues found during the look up.
        """
        policy_bundle = self._operation_policies.get(policy_name)

        if not policy_bundle:
            self._logger.warning(
                "The '{}' policy does not exist.".format(policy_name)
            )
            return None

        if group:
            groups_policy_bundle = policy_bundle.get('groups')
            if not groups_policy_bundle:
                self._logger.debug(
                    "The '{}' policy does not support groups.".format(
                        policy_name
                    )
                )
                return None
            else:
                group_policy = groups_policy_bundle.get(group)
                if not group_policy:
                    self._logger.debug(
                        "The '{}' policy does not support group '{}'.".format(
                            policy_name,
                            group
                        )
                    )
                    return None
                else:
                    return group_policy
        else:
            return policy_bundle.get('preset')
Look up the policy corresponding to the provided policy name and
        group (optional). Log any issues found during the look up.