All Upper II All Upper II
Elementary
English
The mission is in Reviewing Mode. You can't see the solutions Leader Board, but you can see other user solutions through the Random Review after you solve the mission.

Check if a given string has all symbols in upper case. If the string is empty or doesn't have any letter in it - function should return False.

Input: A string.

Output: a boolean.

Example:

is_all_upper('ALL UPPER') == True
is_all_upper('all lower') == False
is_all_upper('mixed UPPER and lower') == False
is_all_upper('') == False

Precondition: a-z, A-Z, 1-9 and spaces