"good" uses of `lambda`:
- key= argument to list.sort()
- the argument to 'filter', 'map'
- capturing variables, more flexibly than `partial` (i.e.: lambda x: lambda y: (x, y))
"good" uses of `lambda`:
- key= argument to list.sort()
- the argument to 'filter', 'map'
- capturing variables, more flexibly than `partial` (i.e.: lambda x: lambda y: (x, y))