not compatible with python 3.13

[ADEL060]

what was the last python version that didn't have compatibility issue with this library?

[asvetlov]

Please elaborate

[dwiel]

Not the OP, but this is what I am seeing:

  × Failed to build `multidict==6.0.4`
  ├─▶ The build backend returned an error
  ╰─▶ Call to `setuptools.build_meta:__legacy__.build_wheel` failed (exit status:
      1)

      [stdout]
      *********************
      * Accelerated build *
      *********************
      running bdist_wheel
      running build
      running build_py
      copying multidict/_multidict_py.py ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      copying multidict/_abc.py ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      copying multidict/__init__.py ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      copying multidict/_multidict_base.py ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      copying multidict/_compat.py ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      running egg_info
      writing multidict.egg-info/PKG-INFO
      writing dependency_links to multidict.egg-info/dependency_links.txt
      writing top-level names to multidict.egg-info/top_level.txt
      reading manifest file 'multidict.egg-info/SOURCES.txt'
      reading manifest template 'MANIFEST.in'
      adding license file 'LICENSE'
      writing manifest file 'multidict.egg-info/SOURCES.txt'
      copying multidict/__init__.pyi ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      copying multidict/py.typed ->
      build/lib.macosx-14.0-arm64-cpython-313/multidict
      running build_ext
      building 'multidict._multidict' extension
      clang -fno-strict-overflow -Wsign-compare -Wunreachable-code
      -fno-common -dynamic -DNDEBUG -g -O3 -Wall
      -I/Users/zdwiel/.cache/uv/builds-v0/.tmpOzkjCF/include
      -I/opt/homebrew/opt/[email protected]/Frameworks/Python.framework/Versions/3.13/include/python3.13
      -c multidict/_multidict.c -o
      build/temp.macosx-14.0-arm64-cpython-313/multidict/_multidict.o -O2 -std=c99
      -Wall -Wsign-compare -Wconversion -fno-strict-aliasing -pedantic

      [stderr]
      warning: no previously-included files matching '*.pyc' found anywhere in
      distribution
      warning: no previously-included files found matching
      'multidict/_multidict.html'
      warning: no previously-included files found matching 'multidict/*.so'
      warning: no previously-included files found matching 'multidict/*.pyd'
      warning: no previously-included files found matching 'multidict/*.pyd'
      no previously-included directories found matching 'docs/_build'
      /Users/zdwiel/.cache/uv/builds-v0/.tmpOzkjCF/lib/python3.13/site-packages/setuptools/command/build_py.py:212:
      _Warning: Package 'multidict._multilib' is absent from the `packages`
      configuration.
      !!


      ********************************************************************************
              ############################
              # Package would be ignored #
              ############################
              Python recognizes 'multidict._multilib' as an importable
      package[^1],
              but it is absent from setuptools' `packages` configuration.

              This leads to an ambiguous overall configuration. If you want to
      distribute this
              package, please make sure that 'multidict._multilib' is explicitly
      added
              to the `packages` configuration field.

              Alternatively, you can also rely on setuptools' discovery methods
              (for example by using
      `find_namespace_packages(...)`/`find_namespace:`
              instead of `find_packages(...)`/`find:`).

              You can read more about "package discovery" on setuptools
      documentation page:

              -
      https://setuptools.pypa.io/en/latest/userguide/package_discovery.html

              If you don't want 'multidict._multilib' to be distributed and are
              already explicitly excluding 'multidict._multilib' via
              `find_namespace_packages(...)/find_namespace` or
      `find_packages(...)/find`,
              you can try to use `exclude_package_data`, or
      `include-package-data=False` in
              combination with a more fine grained `package-data` configuration.

              You can read more about "package data files" on setuptools
      documentation page:

              - https://setuptools.pypa.io/en/latest/userguide/datafiles.html


              [^1]: For Python, any directory (with suitable naming) can be
      imported,
                    even if it does not contain any `.py` files.
                    On the other hand, currently there is no concept of package
      data
                    directory, all directories are treated like packages.

      ********************************************************************************

      !!
        check.warn(importable)
      In file included from multidict/_multidict.c:9:
      multidict/_multilib/iter.h:225:20: warning: a function declaration without a
      prototype is deprecated in all versions of C [-Wstrict-prototypes]
      multidict_iter_init()
                         ^
                          void
      In file included from multidict/_multidict.c:10:
      multidict/_multilib/views.h:388:21: warning: a function declaration without
      a prototype is deprecated in all versions of C [-Wstrict-prototypes]
      multidict_views_init()
                          ^
                           void
      multidict/_multidict.c:453:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:453:10: note: did you mean
      'PyArg_ParseTupleAndKeywords'?
      /opt/homebrew/opt/[email protected]/Frameworks/Python.framework/Versions/3.13/include/python3.13/modsupport.h:11:17:
      note: 'PyArg_ParseTupleAndKeywords' declared here
      PyAPI_FUNC(int) PyArg_ParseTupleAndKeywords(PyObject *, PyObject *,
                      ^
      multidict/_multidict.c:498:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:533:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:712:5: error: call to undeclared function
      'Py_TRASHCAN_SAFE_BEGIN'; ISO C99 and later do not support implicit function
      declarations [-Wimplicit-function-declaration]
          Py_TRASHCAN_SAFE_BEGIN(self);
          ^
      multidict/_multidict.c:718:5: error: call to undeclared function
      'Py_TRASHCAN_SAFE_END'; ISO C99 and later do not support implicit function
      declarations [-Wimplicit-function-declaration]
          Py_TRASHCAN_SAFE_END(self);
          ^
      multidict/_multidict.c:775:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:834:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:870:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:917:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:965:10: error: call to undeclared function
      '_PyArg_ParseStackAndKeywords'; ISO C99 and later do not support implicit
      function declarations [-Wimplicit-function-declaration]
          if (!_PyArg_ParseStackAndKeywords(args, nargs, kwnames, &_parser,
               ^
      multidict/_multidict.c:1684:18: warning: a function declaration without a
      prototype is deprecated in all versions of C [-Wstrict-prototypes]
      PyInit__multidict()
                       ^
                        void
      3 warnings and 10 errors generated.
      error: command '/usr/bin/clang' failed with exit code 1

      hint: This usually indicates a problem with the package or the build
      environment.

The compiler is complaining about _PyArg_ParseStackAndKeywords which appears to have been removed from the private C API and is still used in master branch of this codebase.