input: Write a python function named count_key_transitions(s: str) -> int:
      """
      You are given a 0-indexed string s typed by a user. A key change occurs when the user uses a key different from the previous one. For instance, s = "ab" represents a key change, whereas s = "bBBb" does not.
  
      The function should return the number of key changes the user had to make.
  
      Note: Modifiers like shift or caps lock are not considered a key change. For example, typing 'a' and then 'A' is not counted as a key change.
  
      Examples:
      >>> s = "aAbBcC"
      2
      >>> s = "AaAaAaaA"
      0
  
      Constraints:
      1 <= s.length <= 100
      s is composed solely of upper and lower case English alphabets.
      """
output: def count_key_transitions(s: str) -> int:
      count = 0
      for i in range(1, len(s)):
          if s[i].lower() != s[i - 1].lower():
              count += 1
      return count