class_docstr: :class:`CandidateSelector` that never returns any candidates.
class_docstr_tok: [":","class",":","`","CandidateSelector","`","that","never","returns","any","candidates","."]
code: def candidates(self, user, ratings=None):
      return np.array([], dtype=self.dtype_)
  
imports: import logging
  from collections.abc import Iterable, Sequence
  import pandas
  import numpy
  from ..data import sparse_ratings
  from .None import Predictor, Recommender, CandidateSelector
  from ..util import derivable_rng
  from .bias import Bias
  from .ranking import TopN
label_desc: Use image node_id 2 for calling the EmptyCandidateSelector obj's underlying member method code with example usage: obj.candidates(user, ratings) and returns: np