tokens = argument.split(" ")
if (len(tokens) == 1 and not tokens[0].isdigit()) or \
(len(tokens) > 1 and
- tokens[0] not in {"search", "offset-search"} or
+ (tokens[0] not in {"search", "offset-search"}) or
(tokens[0] == "offset-search" and
((not len(tokens) > 2) or (not tokens[1].isdigit())))):
help()