Kernel getter.
Mimic CPython’s REPL banner.
Recover the shell as it was at start.
Print a string in the shell.
Print error in shell (in red).
Hide shell view.
Launch code in shell.
Pause the shell execution (usefull to wait for event or promise).
Reset the multiline input buffer.
Show shell view.
Show script in shell with content as dropdown (should improve readability).
Resume the shell execution (see pause).
Getter for DOM element.