When the checked program targets Python 3.9 or newer. It is expected that type checkers will flag the deprecated types The redundant types are deprecated as of Python 3.9 but noДeprecation warnings will be issued by the interpreter. These types became redundant in Python 3.9 when theД¬orresponding pre-existing classes were enhanced to support. Standard library classes which also extend Generic This module defines several types that are subclasses of pre-existing What one would normally do in idiomatic dynamically typed Python code. To be explicitly marked to support them, which is unpythonic and unlike The problem with this approach is that a class had This requirement previously also applied to abstract base classes, such as This means that a class A is allowed whereДЄ class B is expected if and only if A is a subclass of B. Initially PEP 484 defined the Python static type system as using Use Any to indicate that a value is dynamically typed. Use object to indicate that a value could be any type in a typesafe # Typechecks, since ints and strs are subclasses of object hash_a ( 42 ) hash_a ( 'foo' ) # Typechecks, since Any is compatible with all types hash_b ( 42 ) hash_b ( 'foo' ) def hash_b ( item : Any ) -> int : # Typechecks item. Vector and list will be treated as interchangeable synonyms:Дef hash_a ( item : object ) -> int : # Fails an object does not have a 'magic' method. PEP 612: Parameter Specification VariablesДЄ type alias is defined by assigning the type to the alias.Introducing types.UnionType and the ability to use PEP 604: Allow writing union types as X | Y.

PEP 593: Flexible function and variable annotations.

PEP 591: Adding a final qualifier to typing.

PEP 589: TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys.

Introducing types.GenericAlias and the ability to use standard

PEP 585: Type Hinting Generics In Standard Collections.

PEP 544: Protocols: Structural subtyping (static duck typing).Introducing syntax for annotating variables outside of function PEP 526: Syntax for Variable Annotations.Number of PEPs have modified and enhanced PythonвЂ™s framework for type Since the initial introduction of type hints in PEP 484 and PEP 483, a Provides backports of these new features to older versions of Python. New features are frequently added to the typing module. In the function greeting, the argument name is expected to be of type Def greeting ( name : str ) -> str : return 'Hello ' + name

Different types of annotations