I did as you asked and I got the same error as you have!
atabak@atabak-X550JX:~/Slicer/Slicer-SuperBuild-Debug/Slicer-build$ ./Slicer --launch /usr/bin/gnome-terminal
Fatal Python error: init_import_size: Failed to import the site module
Python runtime state: initialized
Traceback (most recent call last):
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/site.py”, line 553, in
main()
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/site.py”, line 539, in main
known_paths = addusersitepackages(known_paths)
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/site.py”, line 282, in addusersitepackages
user_site = getusersitepackages()
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/site.py”, line 258, in getusersitepackages
user_base = getuserbase() # this will also set USER_BASE
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/site.py”, line 248, in getuserbase
USER_BASE = get_config_var(‘userbase’)
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/sysconfig.py”, line 601, in get_config_var
return get_config_vars().get(name)
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/sysconfig.py”, line 550, in get_config_vars
_init_posix(_CONFIG_VARS)
File “/home/atabak/Slicer/Slicer-SuperBuild-Debug/python-install/lib/python3.6/sysconfig.py”, line 421, in _init_posix
_temp = import(name, globals(), locals(), [‘build_time_vars’], 0)
ModuleNotFoundError: No module named ‘_sysconfigdata__linux_x86_64-linux-gnu’