function flatten(list) {
newList = []
for (el of list) {
if (!Array.isArray(el))
newList.push(el)
if (Array.isArray(el)) {
for (e of el) {
if (!Array.isArray(e)) {
newList.push(e)
}
else for (i of e) {
newList.push(i)
}
}
}
}
return newList
}