This is a modification of Programmer Dvorak (dvp) for users that do
light-weight Czech typing.  Czech letters with diacritics are
accessible through level 3 shift (such as is typically available
through AltGr).

Another set of two keyboards is for left-handed typing, such that the
right half of the keyboard is accessible via level 3 shift.  One is
for a fairly ordinary keyboard, and another specifically for Kinesis
Advantage.

Use for example like this:
setxkbmap -symbols 'pc+czdvorak(dvp)+level3(ralt_switch)'