{$dict.get {human 2 dog 4} snake 0}
dict.get returns the value associated with a dictionary key. If the key is not found and a fallback value was specified, that value is returned. Otherwise, an error condition is triggered.
{$dict.set $legs snake 0}
dict.set associates a value with a dictionary key. If the key already exists, the value associated with it is replaced.
{$dict.unset $legs snake}
dict.unset removes a key from a dictionary.