code: def _extrema(arr):
      """Return the min and max of an array."""
      return np.min(arr), np.max(arr)
  
imports: import warnings
  from collections.abc import Iterable
  import numpy
  from scipy.stats import gamma
  from nilearn._utils import fill_doc
label_desc: Use image node_id 13 for calling a global function with example usage: _extrema(arr) and returns: np,  np