Is there a name for this type of CES look-alike utility function?

I do not know whether the following utility functions are used a lot but I was wondering whether there was a common name for this type CES like utility function

$$u(z) = left[ left( sum_{j in J_1} z_{j}^{alpha_1}right)^{rho/alpha_1} + left(sum_{j in J_2} z_{j}^{alpha_2}right)^{rho/alpha_2} right]^{1/rho},$$

perhaps it is simply an instance of the CES?

The utility function is defined over two non-overlapping groups $J_1$ and $J_2$ of goods $z_j$. The goods from the two groups are weighted diffrently in the inner CES part by $alpha_1$ and $alpha_2$ respectively.