learn python string isupper() with example

The isupper() method is a built-in method in Python that is used to determine whether all the characters in a string are uppercase letters. It returns True if all the characters in the string are uppercase, and False otherwise.



How to use the isupper() method:

string1 = "HELLO"
string2 = "Hello"
string3 = "123"
string4 = "WORLD123"

print(string1.isupper()) # Output: True
print(string2.isupper()) # Output: False
print(string3.isupper()) # Output: False
print(string4.isupper()) # Output: True

Example 1

Checking Acronyms.

def is_acronym(word):
  if word.isupper():
    print(f"{word} is an acronym.")
    print(f"{word} is not an acronym.")

is_acronym("NASA") # Output: NASA is an acronym.
is_acronym("Python") # Output: Python is not an acronym.

Example 2

Checking all characters are uppercase.

string = "HELLO"
if string.isupper():
  print("All characters are uppercase.")
  print("Not all characters are uppercase.")

Example 3

List comprehension to filter out the strings that are entirely uppercase by applying the isupper() method on each element.

strings = ["HELLO", "WORLD", "Hello", "world"]

uppercase_strings = [s for s in strings if s.isupper()]