code: def _hashable(params):
      """
      Transform list params to tuple format. Ensure that an point is hashable by a python dict.
  
      Parameters
      ----------
      params : numpy array
          array format of parameters
  
      Returns
      -------
      tuple
          tuple format of parameters
      """
      return tuple(map(float, params))
  
file_path: nni/nni/algorithms/hpo/gp_tuner/target_space.py
imports: import numpy
  import nni.parameter_expressions
label_desc: Use image node_id 1 for calling a global function with example usage: _hashable(params) and returns: tuple