The funny thing about the point about similarity between Russian and Ukrainian languages is that linguists will tell you that Ukrainian has more similarities (shared words, and syntactic constructs) with Polish and Belarussian than with Russian.
hash foo &>/dev/null || { echo "foo command not found blabla..." >&2; exit 1; }
more info:
https://stackoverflow.com/questions/592620/how-to-check-if-a...