/snap/classic/7/bin/shell: 44: /snap/classic/7/bin/shell: SUDO_USER: parameter not set
root@liuxg:/snap/bin# ./classic.reset 
root@liuxg:/snap/bin# ./classic.shell
classic not created, please run 'classic.create'
root@liuxg:/snap/bin# ./classic.create 
Creating classic environment
Parallel unsquashfs: Using 4 processors
9623 inodes (10624 blocks) to write

[===============================================================================\] 10624/10624 100%

created 7164 files
created 1325 directories
created 2340 symlinks
created 109 devices
created 0 fifos
chroot: failed to run command '/var/lib/classic/enable.sh': No such file or directory
root@liuxg:/snap/bin# ./classic.shell
/snap/classic/7/bin/shell: 44: /snap/classic/7/bin/shell: SUDO_USER: parameter not set