Python 3.8

Python 3.8.0 (final) was released on the 14 October 2019. The Features for 3.8 are defined in PEP 569 and a detailed description of the changes can be found in What's New in Python 3.8.

Features: Status
PEP 570 Positional-only arguments  
PEP 572 Assignment Expressions  
PEP 574 Pickle protocol 5 with out-of-band data  
PEP 578 Runtime audit hooks  
PEP 587 Python Initialization Configuration  
PEP 590 Vectorcall: a fast calling protocol for CPython  
f-strings support = for self-documenting expressions and debugging Completed

Other Language Changes:

A continue statement was illegal in the finally clause due to a problem with the implementation. In Python 3.8 this restriction was lifted Completed
The bool, int , and fractions.Fraction types now have an as_integer_ratio() method like that found in float and decimal.Decimal  
Constructors of int, float and complex will now use the __index__() special method, if available and the corresponding method __int__(), __float__() or __complex__() is not available  
Added support of N{name} escapes in regular expressions  
Dict and dictviews are now iterable in reversed insertion order using reversed()  
The syntax allowed for keyword names in function calls was further restricted. In particular, f((keyword)=arg) is no longer allowed  
Generalized iterable unpacking in yield and return statements no longer requires enclosing parentheses  
When a comma is missed in code such as [(10, 20) (30, 40)], the compiler displays a SyntaxWarning with a helpful suggestion  
Arithmetic operations between subclasses of or datetime.datetime and datetime.timedelta objects now return an instance of the subclass, rather than the base class  
When the Python interpreter is interrupted by Ctrl-C (SIGINT) and the resulting KeyboardInterrupt exception is not caught, the Python process now exits via a SIGINT signal or with the correct exit code such that the calling process can detect that it died due to a Ctrl-C  
Some advanced styles of programming require updating the types.CodeType object for an existing function  
For integers, the three-argument form of the pow() function now permits the exponent to be negative in the case where the base is relatively prime to the modulus  
Dict comprehensions have been synced-up with dict literals so that the key is computed first and the value second  
The object.__reduce__() method can now return a tuple from two to six elements long  

Changes to built-in modules:

asyncio has graduated from the provisional to stable API Completed
Running python -m asyncio launches a natively async REPL  
The exception asyncio.CancelledError now inherits from BaseException rather than Exception and no longer inherits from concurrent.futures.CancelledError Completed
Added asyncio.Task.get_coro() for getting the wrapped coroutine within an asyncio.Task  
Asyncio tasks can now be named, either by passing the name keyword argument to asyncio.create_task() or the create_task() event loop method, or by calling the set_name() method on the task object  
Added support for Happy Eyeballs to asyncio.loop.create_connection(). To specify the behavior, two new parameters have been added: happy_eyeballs_delay and interleave.  
get_objects() can now receive an optional generation parameter indicating a generation to get objects from. (Note, though, that while gc is a built-in, get_objects() is not implemented for MicroPython)  
Added new function math.dist() for computing Euclidean distance between two points  
Expanded the math.hypot() function to handle multiple dimensions  
Added new function,, as analogous function to sum() that returns the product of a "start" value (default: 1) times an iterable of numbers  
Added two new combinatoric functions math.perm() and math.comb()  
Added a new function math.isqrt() for computing accurate integer square roots without conversion to floating point  
The function math.factorial() no longer accepts arguments that are not int-like Completed
Add new sys.unraisablehook() function which can be overridden to control how "unraisable exceptions" are handled