Fix docs on py27 following changes to the list class

12 jobs for doc_py27 in 10 minutes and 5 seconds (queued for 2 seconds)
Status Name Job ID Coverage
  Build
passed build_linux_27 #64534
conda-linux

00:04:05

passed build_linux_34 #64536
conda-linux

00:05:59

passed build_linux_35 #64538
conda-linux

00:04:50

passed build_macosx_27 #64539
conda-macosx

00:03:23

passed build_macosx_34 #64537
conda-macosx

00:03:58

passed build_macosx_35 #64535
conda-macosx

00:03:05

 
  Test
passed test_linux_27 #64544
conda-linux

00:03:38

85.0%
passed test_linux_34 #64542
conda-linux

00:04:05

92.0%
passed test_linux_35 #64540
conda-linux

00:03:39

85.0%
passed test_macosx_27 #64541
conda-macosx

00:02:52

85.0%
passed test_macosx_34 #64543
conda-macosx

00:03:00

92.0%
passed test_macosx_35 #64545
conda-macosx

00:02:51

85.0%