make a list and limit only the input in single character using python.if the user input two characters it will be invalid

Question

a = []

for i in range (5):
    a.append(input ("Enter only one character: "))
a.sort()
print(a)

a.reverse()
print(a)

This is my code and I don't know how to detect a single character. If a user input two character they will get an error but if the user input single character the input item will be in the list.

Answer 1

Assuming that the OP wants to have a list filled with n valid entries, one solution would be:

a = []
for n in range(5):
    while True:
        answer = input("Enter only one character: ")
        if len(answer) == 1:
            a.append(answer)
            break
        print('I said ONLY ONE character!')

The while True loop will be broken if a valid answer is given, otherwise it will print a reminder to the user and ask for new input. Unless the user is going to give the wrong answer infinite times, this code will ensure the creation of a list with n valid items in it.

Answer 2

You can just check if the length of the string equals to one.

a = []

for i in range(5):
    txt = input('Enter only one character: ')
    if len(txt) == 1: #Checking if length is one
        a.append(txt)
a.sort()
print(a)
a.reverse()
print(a)

Answer 3

a = []

for i in range (5):
    c = input ("Enter only one character: ")
    if len(c) == 1:
        a.append(c)
    else:
        raise ValueError("Input is not a single character")
a.sort()
print(a)

a.reverse()
print(a)