class_docstr: Default implementation of dataset indexing.
  
  DatasetMixin provides the :meth:`__getitem__` operator. The default
  implementation uses :meth:`get_example` to extract each example, and
  combines the results into a list. This mixin makes it easy to implement a
  new dataset that does not support efficient slicing.
  
  Dataset implementation using DatasetMixin still has to provide the
  :meth:`__len__` operator explicitly.
docstr: Returns the i-th example.
  
  Implementations should override it. It should raise :class:`IndexError`
  if the index is invalid.
  
  Args:
      i (int): The index of the example.
  
  Returns:
      The i-th example.
docstr_tok: ["Returns","the","i-th","example",".","Implementations","should","override","it",".","It","should","raise",":","class",":","`","IndexError","`","if","the","index","is","invalid",".","Args",":","i","(","int",")",":","The","index","of","the","example",".","Returns",":","The","i-th","example","."]
code: def get_example(self, i):
      """Returns the i-th example.
  
      Implementations should override it. It should raise :class:`IndexError`
      if the index is invalid.
  
      Args:
          i (int): The index of the example.
  
      Returns:
          The i-th example.
  
      """
      raise NotImplementedError
  
imports: import numpy
  import six
label_desc: Use image node_id 3 for calling the DatasetMixin obj's underlying member method code with example usage: obj.get_example(i) without return types