input: def is_last_char_alphabet(txt):
      '''
      Implement a function that returns True if the final character
      in a provided string is an alphabetical character and stands alone,
      and False otherwise.
      Note: A "word" is defined as a collection of characters separated by spaces.
  
      Examples:
      is_last_char_alphabet("apple pie") ➞ False
      is_last_char_alphabet("apple pi e") ➞ True
      is_last_char_alphabet("apple pi e ") ➞ False
      is_last_char_alphabet("") ➞ False 
      '''
output:     words = txt.split()
      if not words:
          return False
      last_word = words[-1]
      return last_word.isalpha() and len(last_word) == 1