Returns True if string has at least one letter and all characters are uppercase, otherwise returns false.
>>> spam = 'Hello, world!'
>>> spam.isupper()
False
>>> 'HELLO'.isupper()
True
>>> '12345'.isupper()
False
isupper()
Returns True if string has at least one letter and all characters are uppercase, otherwise returns false.
>>> spam = 'Hello, world!'
>>> spam.isupper()
False
>>> 'HELLO'.isupper()
True
>>> '12345'.isupper()
False