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This PR contains the following updates:

| Package | Type | Update | Change |
| [pypa/cibuildwheel]( | action |
minor | `v2.14.1` -> `v2.15.0` |


### Release Notes

<summary>pypa/cibuildwheel (pypa/cibuildwheel)</summary>



- 🌟 CPython 3.12 wheels are now built by default - without the
CIBW_PRERELEASE_PYTHONS flag. It's time to build and upload these wheels
to PyPI! This release includes CPython 3.12.0rc1, which is guaranteed to
be ABI compatible with the final release.
- ✨ Adds musllinux\_1\_2 support - this allows packagers to build for
musl-based Linux distributions on a more recent Alpine image, and a
newer musl libc.



### Configuration

📅 **Schedule**: Branch creation - "on the first day of the month" (UTC),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update


- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box


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PyPI version Supported Python versions PyPI downloads GitHub Actions status codecov DOI Code style: Black

UltraJSON is an ultra fast JSON encoder and decoder written in pure C with bindings for Python 3.8+.

Install with pip:

python -m pip install ujson


May be used as a drop in replacement for most other JSON parsers for Python:

>>> import ujson
>>> ujson.dumps([{"key": "value"}, 81, True])
>>> ujson.loads("""[{"key": "value"}, 81, true]""")
[{'key': 'value'}, 81, True]

Encoder options


Used to enable special encoding of "unsafe" HTML characters into safer Unicode sequences. Default is False:

>>> ujson.dumps("<script>John&Doe", encode_html_chars=True)


Limits output to ASCII and escapes all extended characters above 127. Default is True. If your end format supports UTF-8, setting this option to false is highly recommended to save space:

>>> ujson.dumps("åäö")
>>> ujson.dumps("åäö", ensure_ascii=False)


Controls whether forward slashes (/) are escaped. Default is True:

>>> ujson.dumps("")
>>> ujson.dumps("", escape_forward_slashes=False)


Controls whether indentation ("pretty output") is enabled. Default is 0 (disabled):

>>> ujson.dumps({"foo": "bar"})
>>> print(ujson.dumps({"foo": "bar"}, indent=4))


UltraJSON calls/sec compared to other popular JSON parsers with performance gain specified below each.

Test machine

Linux 5.15.0-1037-azure x86_64 #44-Ubuntu SMP Thu Apr 20 13:19:31 UTC 2023


  • CPython 3.11.3 (main, Apr 6 2023, 07:55:46) [GCC 11.3.0]
  • ujson : 5.7.1.dev26
  • orjson : 3.9.0
  • simplejson : 3.19.1
  • json : 2.0.9
ujson orjson simplejson json
Array with 256 doubles
encode 18,282 79,569 5,681 5,935
decode 28,765 93,283 13,844 13,367
Array with 256 UTF-8 strings
encode 3,457 26,437 3,630 3,653
decode 3,576 4,236 522 1,978
Array with 256 strings
encode 44,769 125,920 21,401 23,565
decode 28,518 75,043 41,496 42,221
Medium complex object
encode 11,672 47,659 3,913 5,729
decode 12,522 23,599 8,007 9,720
Array with 256 True values
encode 110,444 425,919 81,428 84,347
decode 203,430 318,193 146,867 156,249
Array with 256 dict{string, int} pairs
encode 14,170 72,514 3,050 7,079
decode 19,116 27,542 9,374 13,713
Dict with 256 arrays with 256 dict{string, int} pairs
encode 55 282 11 26
decode 48 53 27 34
Dict with 256 arrays with 256 dict{string, int} pairs, outputting sorted keys
encode 42 8 27
Complex object
encode 462 397 444
decode 480 618 177 310

Above metrics are in call/sec, larger is better.

Build options

For those with particular needs, such as Linux distribution packagers, several build options are provided in the form of environment variables.

Debugging symbols


By default, debugging symbols are stripped on Linux platforms. Setting this environment variable with a value of 1 or True disables this behavior.

Using an external or system copy of the double-conversion library

These two environment variables are typically used together, something like:

export UJSON_BUILD_DC_INCLUDES='/usr/include/double-conversion'
export UJSON_BUILD_DC_LIBS='-ldouble-conversion'

Users planning to link against an external shared library should be aware of the ABI-compatibility requirements this introduces when upgrading system libraries or copying compiled wheels to other machines.


One or more directories, delimited by os.pathsep (same as the PATH environment variable), in which to look for double-conversion header files; the default is to use the bundled copy.


Compiler flags needed to link the double-conversion library; the default is to use the bundled copy.