specification

str.capitalize()¶

    Return a copy of the string with its first character capitalized and the rest lowercased.


>>> '\u1ffc', '\u1ff3'
('ῼ', 'ῳ')
>>> '\u1ffc'.isupper()
False
>>> '\u1ff3'.islower()
True
>>> s = '\u1ff3\u1ff3\u1ffc\u1ffc'
>>> s
'ῳῳῼῼ'
>>> s.capitalize()
'ῼῳῼῼ'
>>>

A: lower
B: title

A -> B & !B -> A