QUERY · ISSUE

suggestion: json.dump() does not support default keyword argument

openby xuancong84opened 2025-03-20updated 2025-03-20

enhancement

Description

In the standard Python3 JSON library (https://docs.python.org/3/library/json.html), json.dump() or json.dumps() support the default keyword argument which specifies how to serialize non-standard data types.

default (callable | None) – A function that is called for objects that can’t otherwise be serialized. It should return a JSON encodable version of the object or raise a TypeError. If None (the default), TypeError is raised.

Currently, this is not implemented:

>>> json.dumps({}, default=None)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: extra keyword arguments given

I think this will be a useful addition. Thanks!

Code Size

No response

Implementation

I hope the MicroPython maintainers or community will implement this feature

Code of Conduct

Yes, I agree

CANDIDATE · ISSUE

`flush` keyword argument for `print()`?

openby will-caopened 2021-10-29updated 2025-10-03

enhancementpy-core

CPython 3.3+ supports a flush keyword argument.

https://docs.python.org/3/library/functions.html#print

$ micropython
MicroPython 4fe0332-dirty on 2021-10-27; linux version
Use Ctrl-D to exit, Ctrl-E for paste mode
>>> print(5, flush=True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: extra keyword arguments given