docstr: Tests that arg checker works for a function with varargs.
code: def test_var_args(self):
      """Tests that arg checker works for a function with varargs."""
  
      def func(x, y, *z):
          return x + y + len(z)
  
      self.assertEqual(
          None, xla.check_function_argument_count(func, 2, None)
      )
      self.assertEqual(
          None, xla.check_function_argument_count(func, 3, None)
      )
      self.assertEqual(
          None, xla.check_function_argument_count(func, 4, None)
      )
      self.assertEqual(
          "at least 2 arguments",
          xla.check_function_argument_count(func, 1, None),
      )
      queue = tpu_feed.InfeedQueue(1)
      self.assertEqual(
          None, xla.check_function_argument_count(func, 1, queue)
      )
      self.assertEqual(
          None, xla.check_function_argument_count(func, 2, queue)
      )
      self.assertEqual(
          None, xla.check_function_argument_count(func, 3, queue)
      )
      self.assertEqual(
          "at least 2 arguments",
          xla.check_function_argument_count(func, 0, queue),
      )
  
imports: from absl.testing import parameterized
  from tensorflow.python import summary
  from tensorflow.python.compiler.xla import xla
  from tensorflow.python.eager import def_function
  from tensorflow.python.estimator import model_fn
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import control_flow_ops
  from tensorflow.python.ops import control_flow_util
  from tensorflow.python.ops import logging_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import state_ops
  from tensorflow.python.ops import variable_scope
  from tensorflow.python.ops import while_loop
  from tensorflow.python.platform import test
  from tensorflow.python.tpu import tpu_feed
label_desc: Use image node_id 3 for calling the CheckFunctionArgumentCountTest obj's underlying member method code with example usage: obj.test_var_args() and returns: unknown