However, I’d like it to return only one True if all values satisfy the condition or only one false if any of the values do not satisfy the condition, instead of a list of all values tested one by one.
You have to declare ‘list access’ in your input x (right click) or else the ghpython will run once for every item in your input list and append all solutions to a.
Code would be like this:
a = True
for item in x:
if item > someLowerBound and item < someUpperBound:
continue
else:
a = False
break