code: def test_sequence_max_with_variable_lengths():
      np.random.seed(0)
      a = [-np.ones(i, dtype=np.float32) for i in (7, 11, 13)]
      src = C.sequence.input_variable(
          shape=(1), sequence_axis=C.Axis("Seq")
      )
      out = C.sequence.reduce_max(src)
      val = out.eval({src: a})
      expected = [np.max(a_i) for a_i in a]
      for val_i, expected_i in zip(val, expected):
          assert np.allclose(val_i, expected_i)
  
imports: from __future__ import division
  import numpy
  import pytest
  import cntk
  from .ops_test_utils import cntk_device
  from cntk.tests.test_utils import _to_dense, _to_csr
  from .ops_test_utils import unittest_helper, _test_unary_op, _test_binary_op, AA, precision, PRECISION_TO_TYPE, cntk_device
  from cntk import Value
  from cntk.axis import Axis
  from cntk.internal import sanitize_dtype_cntk
  from ..None import constant
label_desc: Use image node_id 8 for calling a global function with example usage: test_sequence_max_with_variable_lengths() without return types