bambi parser

[aloctavodia]

This allows the use of Bambi models for ppa and predictive_finder. I only tested the code with a couple of simple models.

def a_bambi_model(a0=2, a1=1, b0=2, b1=1):
    x = bmb.Prior("Normal", mu=a0, sigma=a1)
    Intercept = bmb.Prior("Normal", mu=b0, sigma=b1)
    priors = {"x": x, "Intercept": Intercept}

    model = bmb.Model('y ~ x', data, priors=priors)
    
    return Intercept, x, y

target = pz.Normal(2, sigma=3)
pz.predictive_finder(a_bambi_model, target, draws=100, steps=1, engine="bambi")