pl length is 6
  item i int 1
  item s string Bob
  item e float 2.71828
  item j int 42
  item foo string bar
  item pi float 3.14159
pl.contains('e') = True
pl.contains('f') = False
pl[1] = s string Bob
pl['e'] = 2.71828
pl['pi'] = 3.14159
pl['foo'] = bar
after removing 'e', len= 5 pl.contains('e')= False
after sorting:
  item foo string bar
  item i int 1
  item j int 42
  item pi float 3.14159
  item s string Bob
Done.