Checking Sentence Case in String

Question

I wonder how to check for sentence case in string. I know about isupper() method that checks for any uppercase character. But what about sentence case? For example:

def check_string(string):
    <...>
    return result

check_string('This is a proper sentence case.')
True

check_string('THIS IS UPPER CASE')
False

check_string('This string is Clean')
False

Answer 1

A quick trick for this would be using capitalize() and check if it is equal to the original input:

def check_string(my_string):
    cap_string = my_string.capitalize()
    if (cap_string == my_string):
        return True
    return False

Answer 2

def check_string(string): sentences = string.split(".") for sentence in sentences: sentence = sentence.strip() if sentence and (not sentence[0].isupper() or any(filter(lambda x: x.isupper(), sentence[1:]))): return False return True