code: def test_tklmbda_zero_shape(self):
      # When lmbda = 0 the CDF has a simple closed form
      one = mpmath.mpf(1)
      assert_mpmath_equal(
          lambda x: sp.tklmbda(x, 0),
          lambda x: one / (mpmath.exp(-x) + one),
          [Arg()],
          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 16 for calling the TestCDFlib obj's underlying member method code with example usage: obj.test_tklmbda_zero_shape() without return types