code: def inf_fun(self, x):
      return np.inf
  
imports: from numpy.testing import assert_allclose, assert_array_less
  import pytest
  import numpy
  from scipy.optimize import direct, Bounds
label_desc: Use image node_id 5 for calling the TestDIRECT obj's underlying member method code with example usage: obj.inf_fun(x) and returns: np