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Python String | islower () method

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Python has many helper functions in its libraries that always help us with some day to day tasks. Let’s see how the string islower () method works which actually checks if all characters in the string are lowercase.

Syntax: string .islower ()

Parameters: None

Returns: True if all the letters in the string are in lower case and False if even one of them is in upper case.

Code # 1: Demonstration of islower ()

# Python3 demo code
# islower () working

# initialization string

islow_str = " pythonengineering "

not_islow = "Geeksforgeeks"

# check which line
# completely below

print ( "Is pythonengineering full lower? : " + str (islow_str.islower ()))

print ( "Is Geeksforgeeks full lower?: " + str (not_islow.islower ()))


 Is pythonengineering full lower?: True Is Geeksforgeeks full lower?: False 

Practical use: This function can be used in many ways and has many practical uses. such applications are lowercase validation, proper name validation, sentence validation, which requires all lowercase letters. Below is a small example demonstrating the use of the islower () method.

Code # 2: Practical Demonstration islower () method

# Python3 demo code
# using the islower () method

# check proper names.
# capitalized nouns


test_str = " Geeksforgeeks is most rated Computer

Science portal and is highly recommended "

# line splitting

list_str = test_str.split ()


count = 0

# counting lowercase

for i in list_str:

if (i.islower ()):

  count = count + 1

# print proper nouns

print ( "Number of proper nouns in this sentence is:"

+ str ( len (list_str) - count))


 Number of proper nouns in this sentence is: 3 

Python String | islower () method islower: Questions

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