How can Python calculate the number of lowercase letters?

In Python, you can use the islower() method of a string to check if a character is a lowercase letter, and calculate the number of lowercase letters by looping through the string. Here is an example:

def count_lowercase(string):
    count = 0
    for char in string:
        if char.islower():
            count += 1
    return count

string = "Hello World"
lowercase_count = count_lowercase(string)
print(lowercase_count)  # 输出结果为 8

Please note that the string “Hello World” in the example above contains 8 lowercase letters.