# how to create a frozenset

We can check if B is a subset of A with the method .issubset(): As you can see, B is a subset of A because the value returned is True. Frozensets can be created using the function frozenset(). Mypy would complain if importing 'FrozenSet', since it wasn't in __all__. This method is also available for other data structure types like list, dictionary etc…. A frozenset is hashable, meaning every time a frozenset instance is hashed, the same hash value is returned. A frozenset can be created using the frozenset() function. # random dictionary person = {"name": "John", "age": 23, "sex": "male"} fSet = frozenset(person) print('The frozen set is:', fSet) Output. Then in the next step we apply the frozenset function, and try changing the element again. It's as if you had a bag full of rubber balls of different colors. Tip: To create an empty set, you must use the set() function because using an empty set of curly brackets, like this {}, will automatically create an empty dictionary, not an empty set. Solution 2: You should avoid very long set comprehensions in one line to assure that code is user-friendly. Let's look at each of them in detail in today's Python tutorial. Python set and frozenset in python are different. creating a frozenset form an iterable object. Since they cannot contain values of mutable data types, if we try to create a set that contains sets as elements (nested sets), we will see this error: This is an example in IDLE. Its syntax is: class frozenset([iterable]) If the input iterable argument is provided, then forzenset is created from the iterable elements. There are various cases when frozenset is used instead of a python SET. Conclusion. Python frozenset function is a built-in function that is used to create and return an unchangeable frozenset object ( Like set object ). Let's explore these operations. Set comprehension is a more compact and faster way to create sets in Python. The problem is that the sets must contain immutable objects. A Beginners Guide To Learn Linux for Free [with Examples], Red Hat RHCSA/RHCE 8 Certification Study Guide [eBooks], Linux Foundation LFCS and LFCE Certification Study Guide [eBooks]. Let's begin. By contrast, we create a frozenset object using the frozenset class instance constructor frozenset(). Output: frozenset({1, 2, 4.6, 5, 7.8, ‘r’, ‘s’}) The above output consists of set b which is a frozen version of set a. Accessing Elements of a Frozen Set But what happens if we want to check if a set is a proper subset of another? Okay, let’s try to modify the Frozenset … B does not have all the elements of A: To check this, we can use the < comparison operator: If B is a subset of A, then A is a superset of B. You can add, delete, update your set object once it is created. You can create an identical copy of existing set object using copy() method. Frozen set is immutable type. That worked fine for me! You can think of a subset as a "smaller portion" of a set. Let me start by telling you why would you want to use sets in your projects. What sets are and why they are relevant for your projects.