Wrong embedded python version?

[MisterAP]

I'm sure I'm missing something here, but I haven't found anything in searches.

I use Ubuntu 24.04 LTS HWE, patched up to date.
The Ubuntu Python is 3.12
I have a development setup which is up to date.

calibre 8.16.2* embedded-python: True
Linux-6.14.0-37-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-37-generic', '#37~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 10:25:38 UTC 2')
Python 3.11.13

BUT the latest code requires Python 3.13, and I get error:
ImportError: cannot import name 'ShutDown' from 'queue' (/opt/calibre/lib/calibre-extensions/python-lib.bypy.frozen/queue.pyc)

Since I assume no-one can run without 3.13, I must have the wrong setup. How do I get 3.13 as the embedded version?
Or should I be doing something else to use it?

Any help much appreciated.

[gbm]

calibre-debug --gui
calibre 8.16.2  embedded-python: True
Linux-6.14.0-37-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-37-generic', '#37~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 10:25:38 UTC 2')
Python 3.11.14
Interface language: None
EXE path: /opt/calibre/bin/calibre-debug
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && Gather KFX-ZIP (from KFX Input) (2, 27, 1) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 27, 1) && ACSM Input Plugin GUI Extension (0, 1, 0) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Diaps Editing Toolbag (0, 5, 0) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && Goodreads (1, 8, 3) && KFX metadata reader (from KFX Input) (2, 27, 1) && From KFX (2, 27, 1) && KFX Input (2, 27, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Utilities (2, 24, 5) && Modify ePub (1, 8, 8)
QPA platform: xcb
devicePixelRatio: 1.09375
logicalDpi: 96.0 x 96.0
physicalDpi: 84.74714828897338 x 84.69527027027027
ApplicationPaletteChange event ignored
Using calibre Qt style: True
[0.00] Starting up...
[0.00] Showing splash screen...
[1.08] splash screen shown
[1.08] Initializing db...
[1.20] db initialized
[1.20] Constructing main UI...
[1.90] [DEBUG] [koboutilities.config:<module>:72] CreateNewCustomColumn is supported
Loaded cached store plugin for: Kobo at version: 16
ACSM Input: GUI Plugin Genesis!
[2.11] [DEBUG] [koboutilities.action:KoboUtilitiesAction.genesis:117] Running in optimized mode
[2.49] GUI main window shown
EpubMerge: DEBUG: 2025-12-28 11:54:01,071: calibre_plugins.epubmerge.epubmerge_plugin(156): macmenuhack file_path:/home/gbmoore/.config/calibre/plugins/fanficfare_macmenuhack.txt
[2.53] [DEBUG] [koboutilities.config:get_library_config:635] library_config: {'SchemaVersion': 1,
 'profiles': {'Default': {'customColumnOptions': {'currentReadingLocationColumn': '#folder',
                                                  'lastReadColumn': '',
                                                  'percentReadColumn': '',
                                                  'ratingColumn': 'rating',
                                                  'restOfBookEstimateColumn': '',
                                                  'timeSpentReadingColumn': ''},
                          'forDevice': None,
                          'profileName': 'Default',
                          'storeOptionsStore': {'doNotStoreIfReopened': False,
                                                'promptToStore': True,
                                                'storeIfMoreRecent': False,
                                                'storeOnConnect': False},
                          'updateOptionsStore': {'doEarlyFirmwareUpdate': False,
                                                 'doFirmwareUpdateCheck': False,
                                                 'firmwareUpdateCheckLastTime': 0}}},
 'readingPositionChangesStore': {'selectBooksInLibrary': False,
                                 'updeateGoodreadsProgress': False},
 'shelvesColumn': None}
[2.53] [DEBUG] [koboutilities.action:KoboUtilitiesAction.device_driver_name:771] could not load extended driver. Exception= No module named 'calibre_plugins.kobotouch_extended'
[2.53] [DEBUG] [koboutilities.action:KoboUtilitiesAction.set_toolbar_button_tooltip:177] setting to text='Utilities to use with Kobo ereaders

Driver: KoboTouch'
[2.63] main UI initialized...
[2.63] Hiding splash screen
[2.63] splash screen hidden
[2.63] Started up in 2.63 seconds with 1326 books

Check your development setup.

Run calibre without using the development setup.



bernie

Originally Posted by MisterAP

I'm sure I'm missing something here, but I haven't found anything in searches.

I use Ubuntu 24.04 LTS HWE, patched up to date.
The Ubuntu Python is 3.12
I have a development setup which is up to date.

calibre 8.16.2* embedded-python: True
Linux-6.14.0-37-generic-x86_64-with-glibc2.39 Linux ('64bit', 'ELF')
('Linux', '6.14.0-37-generic', '#37~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 10:25:38 UTC 2')
Python 3.11.13

BUT the latest code requires Python 3.13, and I get error:
ImportError: cannot import name 'ShutDown' from 'queue' (/opt/calibre/lib/calibre-extensions/python-lib.bypy.frozen/queue.pyc)

Since I assume no-one can run without 3.13, I must have the wrong setup. How do I get 3.13 as the embedded version?
Or should I be doing something else to use it?

Any help much appreciated.

[MisterAP]

Thanks for that.
I can run the non-development version, but that does not let me use the development environment.
I don't use it very often, but I do need it.

[kovidgoyal]

The next version of calibre will have python 3.14 embedded. For the moment you should stay at the commit before https://github.com/kovidgoyal/calibr...d5821229224253 to run from source.

[kovidgoyal]

I just uploaded binaries with the updated python at: https://download.calibre-ebook.com/preview/

so if you install those you should be fine.

[Comfy.n]

Originally Posted by kovidgoyal

I just uploaded binaries with the updated python at: https://download.calibre-ebook.com/preview/

so if you install those you should be fine.

I'm getting a 403 on windows installers

[MisterAP]

@kovidgoyal Thanks for that. I can wait a while for the update.

[DNSB]

I'm also getting a 403 error on the Windows binaries. The MacOS and Linux binaries seem to download without issue.

[kovidgoyal]

Originally Posted by Comfy.n

I'm getting a 403 on windows installers

Fixed.

[DNSB]

Thanks! Works now other than various plugins throwing errors.

Spoiler:

Failed to initialize plugin: 'C:\\Users\\<user>\\AppData\\Roaming\\calibre\\plu gins\\AZW6 Image Merge.zip'
Traceback (most recent call last):
File "d:\calibre\calibre-master\src\calibre\customize\ui.py", line 833, in initialize_plugins
File "d:\calibre\calibre-master\src\calibre\customize\ui.py", line 87, in load_plugin
File "d:\calibre\calibre-master\src\calibre\customize\zipplugin.py", line 310, in load
File "importlib\__init__.py", line 88, in import_module
File "<frozen importlib._bootstrap>", line 1398, in _gcd_import
File "<frozen importlib._bootstrap>", line 1371, in _find_and_load
File "<frozen importlib._bootstrap>", line 1342, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 938, in _load_unlocked
File "d:\calibre\calibre-master\src\calibre\customize\zipplugin.py", line 209, in exec_module
File "calibre_plugins.azw6_image_merge.__init__", line 9, in <module>
File "d:\calibre\calibre-master\src\calibre\customize\zipplugin.py", line 209, in exec_module
File "calibre_plugins.azw6_image_merge.mobimergehdimage ", line 4, in <module>
ModuleNotFoundError: No module named 'imghdr'
calibre_plugins.baen.__init__:47: SyntaxWarning: "\d" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\d"? A raw string is also an option.
calibre_plugins.baen.__init__:59: SyntaxWarning: "\." is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\."? A raw string is also an option.
calibre_plugins.baen.__init__:198: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.baen.__init__:199: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
ApplicationPaletteChange event ignored
Using calibre Qt style: True
ApplicationPaletteChange event received
Traceback (most recent call last):
File "d:\calibre\calibre-master\src\calibre\gui2\ui.py", line 147, in __init__
File "d:\calibre\calibre-master\src\calibre\gui2\ui.py", line 165, in init_iaction
File "d:\calibre\calibre-master\src\calibre\customize\__init__.py", line 679, in load_actual_plugin
File "importlib\__init__.py", line 88, in import_module
File "<frozen importlib._bootstrap>", line 1398, in _gcd_import
File "<frozen importlib._bootstrap>", line 1371, in _find_and_load
File "<frozen importlib._bootstrap>", line 1342, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 938, in _load_unlocked
File "d:\calibre\calibre-master\src\calibre\customize\zipplugin.py", line 209, in exec_module
File "calibre_plugins.annotations.action", line 11, in <module>
ModuleNotFoundError: No module named 'imp'
calibre_plugins.count_pages.statistics:415: SyntaxWarning: "\D" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\D"? A raw string is also an option.
calibre_plugins.count_pages.statistics:416: SyntaxWarning: "\D" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\D"? A raw string is also an option.
calibre_plugins.find_duplicates.common_menus:50: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
calibre_plugins.job_spy.ui:550: SyntaxWarning: "\J" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\J"? A raw string is also an option.
calibre_plugins.job_spy.ui:2245: SyntaxWarning: "\J" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\J"? A raw string is also an option.
calibre_plugins.job_spy.ui:11864: SyntaxWarning: "\c" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\c"? A raw string is also an option.
calibre_plugins.job_spy.config:148: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.job_spy.config:149: SyntaxWarning: "\[" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\["? A raw string is also an option.
calibre_plugins.job_spy.config:154: SyntaxWarning: "\[" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\["? A raw string is also an option.
calibre_plugins.job_spy.config:156: SyntaxWarning: "\[" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\["? A raw string is also an option.
calibre_plugins.job_spy.config:158: SyntaxWarning: "\[" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\["? A raw string is also an option.
calibre_plugins.job_spy.config:171: SyntaxWarning: "\*" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\*"? A raw string is also an option.
calibre_plugins.koreader.slpp:58: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.koreader.slpp:59: SyntaxWarning: "\w" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\w"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:432: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:432: SyntaxWarning: "\-" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\-"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:432: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:446: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:446: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:462: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:462: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:469: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:469: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.obok_dedrm.obok.obok:668: SyntaxWarning: "\s" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\s"? A raw string is also an option.
calibre_plugins.resize_cover.common_menus:50: SyntaxWarning: "\g" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\g"? A raw string is also an option.
[overdrive_libby/0.2.101*f2fb6d4] Loaded 0 items from file cache C:\Users\<user>\AppData\Roaming\calibre\plugins\ov erdrive_libby.libraries.json
[overdrive_libby/0.2.101*f2fb6d4] Loaded 0 items from file cache C:\Users\<user>\AppData\Roaming\calibre\plugins\ov erdrive_libby.media.json
EpubMerge: DEBUG: 2025-12-29 01:32:36,554: calibre_plugins.epubmerge.epubmerge_plugin(156): macmenuhack file_path:C:\Users\<user>\AppData\Roaming\calibre\ plugins\fanficfare_macmenuhack.txt
FFF: DEBUG: 2025-12-29 01:32:36,577: calibre_plugins.fanficfare_plugin.fff_plugin(218): Plugin FanFicFare macmenuhack file_path:C:\Users\<user>\AppData\Roaming\calibre\ plugins\fanficfare_macmenuhack.txt
calibre Debug log
calibre 8.16.100* embedded-python: True
Windows-11-10.0.26200-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '11', '10.0.26200')
Python 3.14.2
Windows: ('11', '10.0.26200', 'SP0', 'Multiprocessor Free')
Interface language: None
EXE path: C:\Program Files\Calibre2\calibre-debug.exe
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && LCPL Input (0, 0, 5) && Gather KFX-ZIP (from KFX Input) (2, 27, 1) && DeDRM (10, 0, 15) && Package KFX (from KFX Input) (2, 27, 1) && ACSM Input Plugin GUI Extension (0, 1, 0) && Annotations (1, 17, 13) && Apple Books covers (1, 1, 0) && Backup Configuration Folder (1, 1, 2) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Calibre Config Reports (2, 0, 11) && Count Pages (1, 14, 4) && Diaps Editing Toolbag (0, 5, 0) && EpubCheck (0, 2, 6) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && FanFicFare (4, 52, 0) && Find Duplicates (1, 10, 9) && Generate Cover (2, 3, 6) && Goodreads (1, 8, 3) && Job Spy (1, 0, 239) && KFX metadata reader (from KFX Input) (2, 27, 1) && From KFX (2, 27, 1) && KFX Input (2, 27, 1) && Set KFX metadata (from KFX Output) (2, 18, 0) && KFX Output (2, 18, 0) && KOReader Sync (0, 7, 2) && Kindle hi-res covers (0, 5, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Metadata (1, 12, 0) && Kobo Utilities (2, 24, 5) && Modify ePub (1, 8, 8) && Obok DeDRM (10, 0, 9) && Open With (1, 8, 4) && OverDrive Libby (0, 2, 101) && Quality Check (1, 14, 6) && Reading List (1, 15, 6) && Resize Cover (1, 2, 1) && ScrambleEbook (0, 6, 0) && SmartEject (2, 6, 0) && Smashwords Metadata (1, 0, 2)
calibre 8.16.100* embedded-python: True
Windows-11-10.0.26200-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '11', '10.0.26200')
Python 3.14.2
Windows: ('11', '10.0.26200', 'SP0', 'Multiprocessor Free')
Interface language: None
EXE path: C:\Program Files\Calibre2\calibre-debug.exe
Successfully initialized third party plugins: ACSM Input (0, 1, 0) && LCPL Input (0, 0, 5) && Gather KFX-ZIP (from KFX Input) (2, 27, 1) && DeDRM (10, 0, 15) && Package KFX (from KFX Input) (2, 27, 1) && ACSM Input Plugin GUI Extension (0, 1, 0) && Annotations (1, 17, 13) && Apple Books covers (1, 1, 0) && Backup Configuration Folder (1, 1, 2) && Baen (1, 1, 0) && Barnes & Noble (1, 5, 7) && Calibre Config Reports (2, 0, 11) && Count Pages (1, 14, 4) && Diaps Editing Toolbag (0, 5, 0) && EpubCheck (0, 2, 6) && EpubMerge (3, 2, 0) && EpubSplit (3, 12, 0) && FanFicFare (4, 52, 0) && Find Duplicates (1, 10, 9) && Generate Cover (2, 3, 6) && Goodreads (1, 8, 3) && Job Spy (1, 0, 239) && KFX metadata reader (from KFX Input) (2, 27, 1) && From KFX (2, 27, 1) && KFX Input (2, 27, 1) && Set KFX metadata (from KFX Output) (2, 18, 0) && KFX Output (2, 18, 0) && KOReader Sync (0, 7, 2) && Kindle hi-res covers (0, 5, 1) && KindleUnpack - The Plugin (0, 83, 8) && Kobo Metadata (1, 12, 0) && Kobo Utilities (2, 24, 5) && Modify ePub (1, 8, 8) && Obok DeDRM (10, 0, 9) && Open With (1, 8, 4) && OverDrive Libby (0, 2, 101) && Quality Check (1, 14, 6) && Reading List (1, 15, 6) && Resize Cover (1, 2, 1) && ScrambleEbook (0, 6, 0) && SmartEject (2, 6, 0) && Smashwords Metadata (1, 0, 2)
QPA platform: windows
devicePixelRatio: 1.0
logicalDpi: 96.0 x 96.0
physicalDpi: 81.55183946488295 x 81.64285714285714
[0.00] Starting up...
[0.00] Showing splash screen...
[1.15] splash screen shown
[1.15] Initializing db...
[1.18] db initialized
[1.18] Constructing main UI...
[2.26] [DEBUG] [koboutilities.config:<module>:72] CreateNewCustomColumn is supported
DEBUG: 0.0 obok::utilities.py - loading translations
DEBUG: 0.0 obok::dialogs.py - loading translations
DEBUG: 0.0 obok::config.py - loading translations
DEBUG: 0.0 obok::action_err.py - loading translations
qt.webengine.QWebEngineView OK
ACSM Input: GUI Plugin Genesis!
DEBUG: 0.0 koreader:action:KoreaderAction:genesis:start
[2.90] [DEBUG] [koboutilities.action:KoboUtilitiesAction.genesis:1 17] Running in optimized mode
[3.49] GUI main window shown
Job Spy has begun initialization...
Calibre, and hence Job Spy, was gracefully shut down last time? True
Last time daemon started: never
Last time daemon failed: never
Total daemon starts inception_to_date: 0
Total daemon failures inception-to-date: 0
JS: ===>>> change_gui_alternating_row_colors()
Job Spy has finished initialization...
[3.62] [DEBUG] [koboutilities.config:get_library_config:635] library_config: {'SchemaVersion': 1,
'profiles': {'Default': {'customColumnOptions': {'currentReadingLocationColumn': '#koboreadloc',
'lastReadColumn': '#kobolastread',
'percentReadColumn': '#koboreadpct',
'ratingColumn': '#koborating',
'restOfBookEstimateColumn': '#kobo_rest_of_book_estimate',
'timeSpentReadingColumn': '#kobo_time_spent_reading'},
'forDevice': '*Any Device',
'profileName': 'Default',
'storeOptionsStore': {'doNotStoreIfReopened': False,
'promptToStore': False,
'storeIfMoreRecent': False,
'storeOnConnect': True},
'updateOptionsStore': {'doEarlyFirmwareUpdate': False,
'doFirmwareUpdateCheck': False,
'firmwareUpdateCheckLastTime': 0}}},
'readingPositionChangesStore': {'selectBooksInLibrary': False,
'updeateGoodreadsProgress': False},
'shelvesColumn': None}
[3.62] [DEBUG] [koboutilities.action:KoboUtilitiesAction.device_dr iver_name:771] could not load extended driver. Exception= No module named 'calibre_plugins.kobotouch_extended'
[3.62] [DEBUG] [koboutilities.action:KoboUtilitiesAction.set_toolb ar_button_tooltip:177] setting to text='Utilities to use with Kobo ereaders

Driver: KoboTouch'
[3.68] main UI initialized...
[3.68] Hiding splash screen
[3.68] splash screen hidden
[3.68] Started up in 3.68 seconds with 82 books
DEBUG: 32.8 Fetching metadata source hashes...
[67.01] Shutdown starting...
[67.28] [Backup Configuration Folder]: starting backup process
[69.14] [Backup Configuration Folder]: wrote config backup to C:\Users\<user>\Desktop\Calibre Config Backups\backup-calibre\2025-12-29 at 01-33-40.zip. Size: 84,966,688 bytes.
[69.15] [Backup Configuration Folder]: Deleting old config backup file 2025-12-15 at 18-55-32.zip
[69.15] [Backup Configuration Folder]: finished
[71.17] Shutdown complete, quitting...

[kovidgoyal]

imghdr was deprecated years ago and removed from the python stdlib in 3.13 the plugin should be changed to use calibre.utils.imghdr which is much better than the stdlib imghdr ever was anyway.

Same for imp which should be replaced by importlib