code: def test_string_formatting(self):
      actual = Title("timestep {values:.2f}", values=[5e7]).titles
      assert actual == ["timestep 50000000.00"]
  
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 6 for calling the TestTitleBlock obj's underlying member method code with example usage: obj.test_string_formatting() without return types