code: def test_kwarg_throughput(self):
      x = np.array([np.arange(5), np.arange(5)])
      line_block = amp.blocks.Line(
          x, np.random.randn(2, 5), t_axis=1, alpha=0.5
      )
      assert line_block.line.get_alpha() == 0.5
  
imports: from matplotlib.testing import setup
  import numpy
  import numpy.testing
  import matplotlib.pyplot
  import matplotlib
  import packaging.version
  import pytest
  import animatplot
  from tests.tools import animation_compare
  from animatplot.blocks import Block, Title
label_desc: Use image node_id 9 for calling the TestLineBlock obj's underlying member method code with example usage: obj.test_kwarg_throughput() without return types