Having exactly the same problem.
If trying to download covers:
Code:
calibre, version 3.31.0
ERROR: Download failed: Failed to download any covers, click "Show details" for details.
Traceback (most recent call last):
File "site-packages/calibre/utils/ipc/simple_worker.py", line 289, in main
File "site-packages/calibre/ebooks/metadata/sources/worker.py", line 110, in single_covers
File "site-packages/calibre/ebooks/metadata/sources/update.py", line 79, in patch_plugins
File "site-packages/calibre/ebooks/metadata/sources/update.py", line 62, in patch_search_engines
File "<string>", line 11, in <module>
ImportError: No module named polyglot.builtins
If trying to download metadata:
Code:
calibre, version 3.31.0 (darwin, embedded-python: True)
Failed to download metadata: Failed: Download metadata for one book
Starting job: Download metadata for one book
Job: "Download metadata for one book" failed with error:
Traceback (most recent call last):
File "site-packages/calibre/gui2/threaded_jobs.py", line 84, in start_work
File "site-packages/calibre/gui2/metadata/bulk_download.py", line 255, in download
Exception: Failed to download metadata. Original traceback:
Traceback (most recent call last):
File "site-packages/calibre/utils/ipc/simple_worker.py", line 289, in main
File "site-packages/calibre/ebooks/metadata/sources/worker.py", line 55, in main
File "site-packages/calibre/ebooks/metadata/sources/update.py", line 79, in patch_plugins
File "site-packages/calibre/ebooks/metadata/sources/update.py", line 62, in patch_search_engines
File "<string>", line 11, in <module>
ImportError: No module named polyglot.builtins
Called with args: ([1967], u'/var/folders/nl/50d7fqdn6rzdhbmz970z6ncm0000gn/C/calibre_3.31.0_tmp_GhAuRQ/75VK4K_metadata_bulk.log', <calibre.db.legacy.LibraryDatabase object at 0x10a217f10>, True, False, None) {u'abort': <threading._Event object at 0x10eecd210>, u'notifications': <Queue.Queue instance at 0x115d04b48>, u'log': <calibre.utils.logging.GUILog object at 0x10eecd350>}