code: def f(self, n, z):
      return spherical_in(n, z)
  
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_allclose, assert_array_almost_equal, suppress_warnings
  import pytest
  from numpy import sin, cos, sinh, cosh, exp, inf, nan, r_, pi
  from scipy.special import spherical_jn, spherical_yn, spherical_in, spherical_kn
  from scipy.integrate import quad
label_desc: Use image node_id 1 for calling the TestSphericalInDerivatives obj's underlying member method code with example usage: obj.f(n, z) and returns: spherical_in