ModelingToolkit example macro appears not to work

I am trying to set up an ODE System similar to the very first example in ModelingToolkit. When I try to run e.g the code from the first example I get the error `UndefVarError: @named not defined’.

Anyone know what is going on? Here is the code

using ModelingToolkit

@variables t x(t) RHS(t)  # independent and dependent variables
@parameters τ       # parameters
D = Differential(t) # define an operator for the differentiation w.r.t. time

# your first ODE, consisting of a single equation, indicated by ~
@named fol_separate = ODESystem([ RHS  ~ (1 - x)/τ,
                                  D(x) ~ RHS ])

That code works for me. What version of ModelingToolkit are you running? Check with

] st ModelingToolkit

in the REPL, current version seems to be v8.7.1 and was the one I tested with.

Thank you for specifying the version - I manually upgraded to v8.7.1 and it now works