NF = 6
IndexDn = {0,2,4}
IndexUp = {1,3,5}
All     = {0,1,2,3,4,5}

H = 3.0 * NewOperator("Number", NF, All, All, {1,1,1,1,1,1})
  + NewOperator("U", NF, IndexUp, IndexDn, {5.0, 7.0})
  + 0.1 * NewOperator("ldots", NF, IndexUp, IndexDn)
  + 0.2 * NewOperator("Sz", NF, IndexUp, IndexDn)

print(Chop(ShellAverage(H)))