str.islower()
str.islower() is a Python method in the String Methods category. Returns True if all cased characters are lowercase. The syntax is str.islower(). Returns: Boolean. A typical example: "hello".islower() # True
"Hello".islower() # False. A close sibling is str.upper(), which returns a copy of the string with all characters converted to uppercase. A close sibling is str.lower(), which returns a copy of the string with all characters converted to lowercase. A close sibling is str.capitalize(), which returns a copy with the first character capitalized and the rest lowercased. A close sibling is str.title(), which returns a titlecased version where each word starts with uppercase. More about this category: String methods for text manipulation — split, join, replace, format, and more. For a broader walkthrough, read the String Methods guide. Related String Methods entries: str.upper(), str.lower(), str.capitalize(), str.title(), str.strip(), str.lstrip().