code: def exponential_beta(n=2):
      with pm.Model() as model:
          pm.Beta("x", 3, 1, size=n, transform=None)
          pm.Exponential("y", 1, size=n, transform=None)
      return model.initial_point(), model, None
  
imports: from itertools import product
  import numpy
  import pytensor
  import pytensor.tensor
  from pytensor.compile.ops import as_op
  import pymc
  from pymc import Categorical, Metropolis, Model, Normal
  from pymc.pytensorf import floatX_array
label_desc: Use image node_id 14 for calling a global function with example usage: exponential_beta(n) and returns: model,  model,  None