code: def _get_default_ml_hp_tune_opt(num_hps):
      """Return default optimisation method for maximum likelihood."""
      if num_hps > 60:
          return "pdoo"
      else:
          return "direct"
  
imports: from __future__ import division
  from argparse import Namespace
  from itertools import product
  import sys
  import numpy
  from ..distributions.model import Model
  from ..distributions import continuous
  from ..distributions import discrete
  from ..utils.general_utils import stable_cholesky, draw_gaussian_samples, project_symmetric_to_psd_cone, solve_lower_triangular, solve_upper_triangular
  from ..utils.oper_utils import direct_ft_maximise, pdoo_maximise, random_maximise, random_sample_cts_dscr
  from ..utils.option_handler import get_option_specs, load_options
  from ..utils.reporters import get_reporter
label_desc: Use image node_id 2 for calling a global function with example usage: _get_default_ml_hp_tune_opt(num_hps) and returns: str, str