Is your feature request related to a problem? Please describe.
Let's say goodbye to our old friend "Specified Qt version is unknown" and their partners. They always confuse our users.
$ aqt install-qt linux desktop 9.9.9
INFO : aqtinstall(aqt) v3.1.11 on Python 3.10.12 [CPython GCC 11.4.0]
WARNING : Specified Qt version "9.9.9" did not exist when this version of aqtinstall was released. This may not install properly, but we will try our best.
WARNING : Failed to download checksum for the file 'Updates.xml'. This may happen on unofficial mirrors.
ERROR : Failed to locate XML data for Qt version '9.9.9'.
==============================Suggested follow-up:==============================
* Please use 'aqt list-qt linux desktop' to show versions available.
$ aqt install-qt linux desktop 9.9.9
INFO : aqtinstall(aqt) v2.2.4 on Python 3.10.12 [CPython GCC 11.4.0]
WARNING : Specified Qt version is unknown: 9.9.9.
ERROR : Failed to locate XML data for Qt version '9.9.9'.
==============================Suggested follow-up:==============================
* Please use 'aqt list-qt linux desktop' to show versions available.
$ aqt install 9.9.9 linux desktop
aqtinstall(aqt) v1.2.5 on Python 3.10.12 [CPython GCC 11.4.0]
Specified Qt version is unknown: 9.9.9.
Download error when access to https://download.qt.io/online/qtsdkrepository/linux_x64/desktop/qt9_999/Updates.xml
Server response code: 404, reason: Not Found
Describe the solution you'd like
$ aqt install 9.9.9 linux desktop
aqtinstall(aqt) v...
WARNING : Failed to download checksum for the file 'Updates.xml'. This may happen on unofficial mirrors.
ERROR : Failed to locate XML data for Qt version '9.9.9'.
============================================================
Available Qt versions: 5.15.2, 6.0.4...
Is your feature request related to a problem? Please describe.
Let's say goodbye to our old friend "Specified Qt version is unknown" and their partners. They always confuse our users.
Describe the solution you'd like
Describe alternatives you've considered
None.
Additional context
From What's the purpose of making the "combinations.json" file? · miurahr/aqtinstall · Discussion #747.