code: def indices_from_labels(labels, validate=True):
      if validate:
          _validate_labels(labels)
  
      return np.unique(labels[labels != 0])
  
imports: from enum import Enum
  import numpy
  from numpy.random.mtrand import RandomState
  import scipy.sparse
  import centrosome.index
label_desc: Use image node_id 13 for calling a global function with example usage: indices_from_labels(labels, validate) and returns: np