julia> T = Tensor(rand(2, 2, 2, 2), (:i, :j, :k, :l))
2×2×2×2 Tensor{Float64, 4, Array{Float64, 4}}:
[:, :, 1, 1] =
 0.203794  0.890273
 0.637581  0.756578

[:, :, 2, 1] =
 0.649558  0.408352
 0.23286   0.51925

[:, :, 1, 2] =
 0.297936  0.153945
 0.546996  0.484567

[:, :, 2, 2] =
 0.561427  0.422659
 0.968955  0.703751

julia> T[i = 1]
2×2×2 Array{Float64, 3}:
[:, :, 1] =
 0.203794  0.649558
 0.890273  0.408352

[:, :, 2] =
 0.297936  0.561427
 0.153945  0.422659