code: def test_stdtr(self):
      # Ideally the left endpoint for Arg() should be 0.
      assert_mpmath_equal(
          sp.stdtr,
          _student_t_cdf,
          [IntArg(1, 100), Arg(1e-10, np.inf)],
          rtol=1e-7,
      )
  
imports: import itertools
  import numpy
  from numpy.testing import assert_equal, assert_allclose
  import pytest
  import scipy.special
  from scipy.special._testutils import MissingModule, check_version, FuncData
  from scipy.special._mptestutils import Arg, IntArg, get_args, mpf2float, assert_mpmath_equal
label_desc: Use image node_id 9 for calling the TestCDFlib obj's underlying member method code with example usage: obj.test_stdtr() without return types