Changed assertIs to assertEqual
Changed assertIs to assertEqual

cellml/libcellml,hsorby/libcellml,cellml/libcellml,nickerso/libcellml,hsorby/libcellml,hsorby/libcellml,hsorby/libcellml,MichaelClerx/libcellml,nickerso/libcellml,cellml/libcellml,cellml/libcellml,MichaelClerx/libcellml,MichaelClerx/libcellml,nickerso/libcellml,nickerso/libcellml