# A set is a container like a list or a dict, except that *each element can be stored only once*.
# Think of it like the keys of a dict, except there isn't any value associated with each key.
# I use Sets to count digits below. Feel free to look up the Set online and try it in the
# interpreter.
# A set is a container like a list or a dict, except that *each element can be stored only once*.
# Think of it like the keys of a dict, except there isn't any value associated with each key.
# I use Sets to count digits below. Feel free to look up the Set online and try it in the
# interpreter.