'If statement within for statement is only outputting the print statement of the else portion even though conditions met in if and elif parts

I am trying to get an if/else statement to run in a for loop. Despite the argument meeting the criteria for all statements above it, the output is the else portion. Here is my code:

import string

print(string.ascii_lowercase)
print(string.ascii_uppercase)
print(string.ascii_letters)
print(string.digits)
print(string.punctuation)

my_string = '4n%$P9'
  
for index in range(0, len(my_string), 1):
  if my_string in string.ascii_lowercase:
    print("'{}' is a lowercase letter.".format(my_string))
  elif my_string in string.ascii_uppercase:
    print("'{}' is an uppercase letter.".format(my_string))
  elif my_string in string.digits: 
    print("'{}' is a digit in arabic.".format(my_string))
  elif my_string in string.punctuation:
    print("'{}' is a punctuation mark.".format(my_string))
  else:
    print("Does not compute.")

The output is this:

abcdefghijklmnopqrstuvwxyz
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
0123456789
!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~
Does not compute.
Does not compute.
Does not compute.
Does not compute.
Does not compute.
Does not compute.

I'm not getting a syntax error so I am wondering, am I not using the correct keywords? Is the logic out of order?

pythonfor-loopif-statement


Solution 1:[1]

The problem isn't with the if statements so much as your for loop. It looks like you want to iterate over each character in my_string and test it separately, not test my_string all at once:

for c in my_string:
    if c in string.ascii_lowercase:
        print(f"'{c}' is a lowercase letter.")
    elif c in string.ascii_uppercase:
        print(f"'{c}' is an uppercase letter.")
    elif c in string.digits: 
        print(f"'{c}' is a digit in arabic.")
    elif c in string.punctuation:
        print(f"'{c}' is a punctuation mark.")
    else:
        print(f"'{c}' does not compute.")

prints:

'4' is a digit in arabic.
'n' is a lowercase letter.
'%' is a punctuation mark.
'$' is a punctuation mark.
'P' is an uppercase letter.
'9' is a digit in arabic.

Note that printing c as part of the "does not compute" message allows you to see what character didn't compute -- if you had done this with my_string in your original code, you would have seen:

'4n%$P9' does not compute.
'4n%$P9' does not compute.
'4n%$P9' does not compute.
'4n%$P9' does not compute.
'4n%$P9' does not compute.
'4n%$P9' does not compute.

which would have been a good clue as to what the problem was!

Solution 2:[2]

You are checking whether the entire string is a substring of each of the constants from the string module. You want to perform that check for each character in the string, like so:

import string

my_string = '4n%$P9'
  
for char in my_string:
  if char in string.ascii_lowercase:
    print("'{}' is a lowercase letter.".format(char))
  elif char in string.ascii_uppercase:
    print("'{}' is an uppercase letter.".format(char))
  elif char in string.digits: 
    print("'{}' is a digit in arabic.".format(char))
  elif char in string.punctuation:
    print("'{}' is a punctuation mark.".format(char))
  else:
    print("Does not compute.")

This outputs:

'4' is a digit in arabic.
'n' is a lowercase letter.
'%' is a punctuation mark.
'$' is a punctuation mark.
'P' is an uppercase letter.
'9' is a digit in arabic.

Solution 3:[3]

You are trying to compare if an entire string is in string.ascii_lowercase, not just the letters, you need to actually run my_string[index].

import string

print(string.ascii_lowercase)
print(string.ascii_uppercase)
print(string.ascii_letters)
print(string.digits)
print(string.punctuation)

my_string = '4n%$P9'
  
for index in range(0, len(my_string), 1):
  if my_string[index] in string.ascii_lowercase:
    print("'{}' is a lowercase letter.".format(my_string[index]))
  elif my_string[index] in string.ascii_uppercase:
    print("'{}' is an uppercase letter.".format(my_string[index]))
  elif my_string[index] in string.digits: 
    print("'{}' is a digit in arabic.".format(my_string[index]))
  elif my_string[index] in string.punctuation:
    print("'{}' is a punctuation mark.".format(my_string[index]))
  else:
    print("Does not compute.")

Sources

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Source: Stack Overflow

Solution Source
Solution 1 Samwise
Solution 2 BrokenBenchmark
Solution 3

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