Examples of random() in custom distribution?

Questions
5

I tried to implement the method for a normal distribution (for sake of example), but I get the error 'numpy.ndarray' object is not callable. I created a notebook here. Briefly, my random method is:

def normal_rng(mu, sd, point=None, size=None):
    # draw a numerical value for the parameters
    mu_, sd_ = draw_values([mu, sd], point=point)
    
    size = 1 if size is None else size
    
    return generate_samples(scipy.stats.norm.rvs, loc=mu_, scale=sd_, size=size, broadcast_shape=(size,))

and it is called in DensityDist as:

likelihood = pm.DensityDist('likelihood', normal_logp(mu, sd), observed=y, random=normal_rng(mu, sd))