let dup = new Map();
	function coalesce(a) {
		if(a === null || a === undefined) {
			return '';
		} else {
			return a;
		}
	}

			let w = dup.get(coalesce(producer) + coalesce(brand) + join_name + e[i][0].type);
			if(w === undefined) {
				dup.set(coalesce(producer) + coalesce(brand) + join_name + e[i][0].type, new Set([e[i][0].handle]));
			} else {
				w.add(e[i][0].handle);
			}

	for(let [key, value] of dup) {
		if(value.size > 1) {
			console.log(key, value);
		}
	}