dict.update() return the updated dict instead of None

[AL3X-69]

BPO	40319
Nosy	@corona10, @tirkarthi, @AL3X-69

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2020-04-18.13:26:55.634>
created_at = <Date 2020-04-18.11:57:55.598>
labels = ['type-feature', '3.8']
title = 'dict.update() return the updated dict instead of None'
updated_at = <Date 2020-04-18.13:26:55.625>
user = 'https://github.com/AL3X-69'

bugs.python.org fields:

activity = <Date 2020-04-18.13:26:55.625>
actor = 'SilentGhost'
assignee = 'none'
closed = True
closed_date = <Date 2020-04-18.13:26:55.634>
closer = 'SilentGhost'
components = []
creation = <Date 2020-04-18.11:57:55.598>
creator = 'AL3X_69'
dependencies = []
files = []
hgrepos = []
issue_num = 40319
keywords = []
message_count = 5.0
messages = ['366703', '366704', '366705', '366706', '366710']
nosy_count = 4.0
nosy_names = ['SilentGhost', 'corona10', 'xtreak', 'AL3X_69']
pr_nums = []
priority = 'normal'
resolution = 'rejected'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue40319'
versions = ['Python 3.8']

[AL3X-69]

When a dict is updated with update(), instead of return None, it will return the updated dict.

example:

>>> a = {"test": 1}
>>> b = {"type": 2}
>>> c = a.update(b)
>>> print(c)
{"test": 1, "type": 1}

[tirkarthi]

Can you please print the output of python -v? Using python 3.8.0 on Linux returns None for update method.

[corona10]

Python 3.9.0a5+ (heads/master:c606624af8, Apr 18 2020, 18:42:51)
[Clang 11.0.3 (clang-1103.0.32.29)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> a = {"test": 1}
>>> b = {"type": 2}
>>> c = a.update(b)
>>> print(c)
None

on macOS master branch, the issue is not reproducible.

[corona10]

Python 3.8.2+ (heads/3.8:c496e29c2b, Apr 18 2020, 21:42:41)
[Clang 11.0.3 (clang-1103.0.32.29)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> a = {"test": 1}
>>> b = {"type": 2}
>>> c = a.update(b)
>>> print(c)
None

[SilentGhost]

This looks like a proposed "enhancement" rather than a bug report. Unfortunately, this is not possible for a myriad of reasons, from backward compatibility to overall use of mutating methods in Python.