code: def get_factor(self, rng):
      if self._log_factor is None:
          return 1.0
      return np.exp(rng.uniform(-self._log_factor, self._log_factor))
  
file_path: emcee/src/emcee/moves/gaussian.py
imports: import numpy
  from .mh import MHMove
label_desc: Use image node_id 2 for calling the _isotropic_proposal obj's underlying member method code with example usage: obj.get_factor(rng) and returns: np, int