code: def normal_log_prob(params):
      return -0.5 * np.sum(params**2)
  
file_path: emcee/src/emcee/tests/unit/test_backends.py
imports: import os
  from itertools import product
  from os.path import join
  import numpy
  import pytest
  from emcee import EnsembleSampler, State, backends
  from emcee.backends.hdf import does_hdf5_support_longdouble
label_desc: Use image node_id 1 for calling a global function with example usage: normal_log_prob(params) and returns: unknown