meson: import python module

- Use import to find Python installation.
- Run macos-sdk-version.py with Python provided by meson.

This fixes an error when meson and python-packaging are installed from
Homebrew. Currently, the Python executable from [email protected] is installed as
python3.12 so python3 is referring to system installation, which may not
have packaging module. meson can provide the correct executable via import.

meson.build

@@ -13,7 +13,7 @@ project('mpv',
 
 build_root = meson.project_build_root()
 source_root = meson.project_source_root()
-python = find_program('python3')
+python = import('python').find_installation()
 
 # ffmpeg
 libavcodec = dependency('libavcodec', version: '>= 58.134.100')
@@ -1475,7 +1475,10 @@ endif
 macos_sdk_path = ''
 macos_sdk_version = '0.0'
 if darwin and macos_sdk_version_py.found()
-    macos_sdk_info = run_command(macos_sdk_version_py, check: true).stdout().split(',')
+    # Execute macos-sdk-version.py with Python provided by meson.
+    # In some cases, Python executable with the necessary modules might not refer to python3
+    # (e.g. [email protected] and python-packaging Homebrew packages).
+    macos_sdk_info = run_command(python, macos_sdk_version_py, check: true).stdout().split(',')
     macos_sdk_path = macos_sdk_info[0].strip()
     macos_sdk_version = macos_sdk_info[1]
 endif