--- title: Learn About Python Sets --- `Set`s in Python are a type of mutable but unordered data structure, which can only contain *unique* elements. **Creation:** `set` literal: Curly brackets, `{}`, *cannot* be used to create an empty set: ```python >>> not_set = {} # set constructor must be used to make empty sets. >>> type(not_set) # Empty curly brackets create empty dictionaries. ``` You can only create an empty set by using the `set()` method. ```python >>> example_set = set() >>> type(example_set) ``` However, if elements are included within the curly brackets, then it would be acceptable syntax to create a set. ```python >>> example_set_2 = {1, 2, 3} >>> type(example_set_2) ````