the program finds the number of all repeated characters, case insensitive, in the string and forms a list of the number of repeated and single characters in ascending order

def count_characters(string):
    # Write your code here
    count = {}
    for char in string:
        if char.lower() in count:
            count[char.lower()] += 1
            
        else:
            count[char.lower()] = 1
        
    new_list = []
    for key in sorted(count):
        new_list.append((count[key], key))
        
    return new_list