code: def testGetSelectable(
      self,
      masking_inputs,
      expected_selectable,
      num_to_select=2,
      unselectable_ids=None,
      axis=1,
      description="",
  ):
      masking_inputs = ragged_factory_ops.constant(masking_inputs)
      item_selector = item_selector_ops.FirstNItemSelector(
          num_to_select=num_to_select, unselectable_ids=unselectable_ids
      )
      selectable = item_selector.get_selectable(masking_inputs, axis)
      actual_selection = ragged_array_ops.boolean_mask(
          masking_inputs, selectable
      )
      self.assertAllEqual(actual_selection, expected_selectable)
  
imports: import functools
  from absl.testing import parameterized
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops.ragged import ragged_array_ops
  from tensorflow.python.ops.ragged import ragged_factory_ops
  from tensorflow.python.platform import test
  from tensorflow_text.python.ops import item_selector_ops
label_desc: Use image node_id 1 for calling the FirstNItemSelectorTest obj's underlying member method code with example usage: obj.testGetSelectable(masking_inputs, expected_selectable, num_to_select, unselectable_ids, axis, description) without return types