code: def fit(self, verbose=True):
          
          if not self._isfixed("logistic"):
              self._maximize_scalar(desc="LMM", rtol=1e-6, atol=1e-6, verbose=verbose)
  
          if not self._fix["beta"]:
              self._update_beta()
  
          if not self._fix["scale"]:
              self._update_scale()
docs: Maximise the marginal likelihood.
  
          Parameters
          ----------
          verbose : bool, optional
              ``True`` for progress output; ``False`` otherwise.
              Defaults to ``True``.