KwickClips Python · 42 sec · free
Why is the length of {3, 1, 3, 2, 1} three?
Short answer. A set keeps only unique items.
How do you write an empty set?
set().
Remember
| Set: unique items in { } |
| Duplicates vanish |
| Empty set is set(), not {} |
Five numbers, length three. Why? A set keeps only unique items. Python hashes each value. Equal values share a code, so copies are not stored. A set holds unique items. Duplicates vanish. An empty set is set with round brackets.
This clip is from the full lesson: Sets and Set Operations — 7 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: Programming All levels Python
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