list(list("L1-x=1","y=2"),
     list("L1-x=root_of(x_**6 + x_ + 1,x_,tag_1)","x=1"),
     list(list("L2-a+b","b+c","c+d",
               list("L3-xyz"," def")),
          list("L2-b+c","b+a",
               list("L3-uvw"," ghi"),"d+c")),
     list(list("L2-m+n","o+p","p+q",
               list("L3-yzx"," efd")),
          list("L2-n+m","p+o",
               list("L3-vwu"," hig"),"k*l")),
     list(list("L2-e*f","g/h","i-j",
               list("L3-zxy"," fde")),
          list("L2-b*c","b/a",
               list("L3-wuv","igh"),"l/k")),
     list(list("L2-x=2.12","y=0","z=-2.12"),
          list("L2-x=-2.12","y=0","z=2.12"),
          list("L2-x=0","y=2.12","z=-2.12"),
          list("L2-x=0","y=-2.12","z=2.12")))
