def num_examples_per_epoch(split):
  """Returns the number of examples in the data set.
  Args:
    split: name of the split, "train" or "validation".
  Raises:
    ValueError: if split name is incorrect.
  Returns:
    Number of example in the split.
  """
  if split.lower().startswith('train'):
    return 100000
  elif split.lower().startswith('validation'):
    return 10000
  else:
    raise ValueError('Invalid split: %s' % split)