async fn group_metadata_operation(
source: &CommandSource,
group: String,
expression: PermissionMetadataExpression,
value: Option<PermissionMetadataValue>,
) -> Result<OperationResult, CommandSyntaxError>async fn group_metadata_operation(
source: &CommandSource,
group: String,
expression: PermissionMetadataExpression,
value: Option<PermissionMetadataValue>,
) -> Result<OperationResult, CommandSyntaxError>