Question: How do I fix the following error when setting up the Weyl metric?

restart; with(Physics);
Setup(mathematicalnotation = true);
                 [mathematicalnotation = true]
Setup(signature = `-+++`);
                     [signature = - + + +]
Coordinates(M = [t, rho, z, phi]);

  Default differentiation variables for d_, D_ and dAlembertian 

   are: (Mequals(t,ρ,z,φ))
 Systems of spacetime Coordinates are: (Mequals(t,ρ,z,φ))
ds2 := -exp(2*psi(rho, z))*d*(t^2)+exp(2*gamma(rho, z)-2*psi(rho, z))*(drho^2+dz^2)+exp(-2*psi(rho, z))*(rho^2)*(dphi^2);
    ds2 := -exp(2 psi(rho, z)) d t 

                                              /    2     2\
       + exp(2 gamma(rho, z) - 2 psi(rho, z)) \drho  + dz /

                                2     2
       + exp(-2 psi(rho, z)) rho  dphi 
Setup(metric = ds2);
Error, (in Physics:-Setup) expected the metric as an expression quadratic in [d_(t), d_(rho), d_(z), d_(phi)], or square Matrix, Array or table with 4 lines and 4 columns; or a set with the nonzero components of such a matrix; received: -exp(2*psi(rho, z))*d*t^2+exp(2*gamma(rho, z)-2*psi(rho, z))*(drho^2+dz^2)+exp(-2*psi(rho, z))*rho^2*dphi^2

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