code: def normal_log_prob(params):
      return -0.5 * np.sum(params**2)
  
imports: import pickle
  from itertools import islice, product
  import numpy
  import pytest
  from emcee import EnsembleSampler, backends, moves, walkers_independent
label_desc: Use image node_id 1 for calling a global function with example usage: normal_log_prob(params) and returns: unknown