code: def testInvalidN(self):
      with self.assertRaisesRegex(
          (ValueError, errors.InvalidArgumentError),
          "non-negative but is -1",
      ):
          nn_ops.nth_element([5], -1)
      with self.assertRaisesRegex(
          (ValueError, errors.InvalidArgumentError),
          "scalar but has rank 1",
      ):
          nn_ops.nth_element([5, 6, 3], [1])
  
      # Test with placeholders
      with ops.Graph().as_default():
          with self.session(use_gpu=False):
              n = array_ops.placeholder(dtypes.int32)
              values = nn_ops.nth_element([5], n)
              with self.assertRaisesOpError("non-negative but is -1"):
                  values.eval(feed_dict={n: -1})
  
imports: import numpy
  from tensorflow.python.eager import backprop
  from tensorflow.python.eager import context
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import gradients_impl
  from tensorflow.python.ops import nn_ops
  import tensorflow.python.ops.nn_grad
  from tensorflow.python.platform import test
label_desc: Use image node_id 12 for calling the NthElementTest obj's underlying member method code with example usage: obj.testInvalidN() without return types