code: def __init__(self):
      self._latent = None
      self._conditional = None
  
imports: from collections import defaultdict
  import torch
  import pyro.distributions
  from pyro import poutine
  from pyro.distributions.util import sum_leftmost
  from pyro.poutine.messenger import Messenger
  from pyro.poutine.util import site_is_subsample
label_desc: Use image node_id 1 to create a new BetaBinomialPair object  with example: obj = BetaBinomialPair()