code: def _isSingleCharacter(keychr):
          
          if not keychr:
              return False
          # Regular character case.
          if len(keychr) == 1:
              return True
          # Tagged character case.
          return keychr.count('<') == 1 and keychr.count('>') == 1 and \
                 keychr[0] == '<' and keychr[-1] == '>'
docs: Check whether given keyboard character is a single character.
  
          Parameters: key character which will be checked.
          Returns: True when given key character is a single character.