The following errors are most likely due to Calibre changing from using Python 2 to Python 3.
calibre, version 5.10.1
ERROR: Install plugin failed: A problem occurred while installing this plugin. This plugin will now be uninstalled. Please post the error message in details below into the forum thread for this plugin and restart calibre.
Traceback (most recent call last):
File "calibre\gui2\dialogs\plugin_updater.py", line 709, in _install_clicked
File "calibre\customize\ui.py", line 472, in add_plugin
File "calibre\customize\ui.py", line 61, in load_plugin
File "calibre\customize\zipplugin.py", line 293, in load
File "importlib\__init__.py", line 127, in import_module
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "calibre\customize\zipplugin.py", line 192, in exec_module
File "calibre_plugins.biblionetka.__init__", line 11, in <module>
ModuleNotFoundError: No module named 'Queue'