def METHOD_NAME(self, rule_exp) -> bool:
    """
    Checks whether the storage system name allowed to use again.
    This function executes an OpenShift command to retrieve the names of all existing storage systems
    in all namespaces.
    It then checks whether the name of the existed storage system would be allowed to use.
    Args:
        rule_exp (str): the rule requested to be checked. rule_exp text should match the text from validation popup
    Returns:
        bool: True if not allowed to use duplicated storage system name, False otherwise.
    """
    existing_storage_systems_names = str(
        OCP().exec_oc_cmd(
            "get storageclass --all-namespaces -o custom-columns=':metadata.name'"
        )
    )
    return self._check_resource_name_not_exists_rule(
        existing_storage_systems_names, rule_exp
    )