Simscape component in two-phase fluid domain

Pressure source simscape component in two-phase fluid domain uses function <foundation.two_phase_fluid.sources.isentropic_relation> - see below. Where I can find this and other two-phase fluid domain functions for building custom simscape blocks?

Thank you in advance

intermediates (Access = private, ExternalAccess = none)

% Compute change in specific entropy

[Ds_AB, ht_in_A, ht_out_B] = foundation.two_phase_fluid.sources.isentropic_relation( ...

A.p, B.p, u_in_A, u_out_B, mdot_A, area_A, area_B, ...

A.u_min, A.u_max, A.unorm_TLU, A.p_TLU, A.v_TLU, A.s_TLU, A.u_sat_liq_TLU, A.u_sat_vap_TLU);

[Ds_BA, ht_in_B, ht_out_A] = foundation.two_phase_fluid.sources.isentropic_relation( ...

B.p, A.p, u_in_B, u_out_A, mdot_B, area_B, area_A, ...

A.u_min, A.u_max, A.unorm_TLU, A.p_TLU, A.v_TLU, A.s_TLU, A.u_sat_liq_TLU, A.u_sat_vap_TLU);