def test_nextitem_previtem_chain(hist):
 assert (hist.start('f') == 'fifth')
 assert (hist.previtem() == 'fourth')
 assert (hist.previtem() == 'first')
 assert (hist.nextitem() == 'fourth')

def test_nextitem_previtem_chain ( hist ) : assert ( hist . start ( 'f' ) == 'fifth' ) assert ( hist . previtem ( ) == 'fourth' ) assert ( hist . previtem ( ) == 'first' ) assert ( hist . nextitem ( ) == 'fourth' )
test a combination of nextitem and previtem statements .