code: def terminal_type(cls):
          
          what = sys.platform
  
          kind = 'UNDEFINED_TERMINAL_TYPE'
          if 'linux' in what:
              kind = 'linux'
          elif 'darwin' in what:
              kind = 'darwin'
          elif 'cygwin' in what:
              kind = 'cygwin'
          elif 'windows' in what:
              kind = 'windows'
  
          return kind
docs: returns  darwin, cygwin, cmd, or linux