code: def test_expint():
      from sympy.functions.elementary.miscellaneous import Max
      from sympy.functions.special.error_functions import Ci, E1, Si
      from sympy.simplify.simplify import simplify
  
      aneg = Symbol("a", negative=True)
      u = Symbol("u", polar=True)
  
      assert mellin_transform(E1(x), x, s) == (
          gamma(s) / s,
          (0, oo),
          True,
      )
      assert inverse_mellin_transform(
          gamma(s) / s, s, x, (0, oo)
      ).rewrite(expint).expand() == E1(x)
      assert mellin_transform(expint(a, x), x, s) == (
          gamma(s) / (a + s - 1),
          (Max(1 - re(a), 0), oo),
          True,
      )
      # XXX IMT has hickups with complicated strips ...
      assert simplify(
          unpolarify(
              inverse_mellin_transform(
                  gamma(s) / (aneg + s - 1), s, x, (1 - aneg, oo)
              )
              .rewrite(expint)
              .expand(func=True)
          )
      ) == expint(aneg, x)
  
      assert mellin_transform(Si(x), x, s) == (
          -(2**s)
          * sqrt(pi)
          * gamma(s / 2 + S.Half)
          / (2 * s * gamma(-s / 2 + 1)),
          (-1, 0),
          True,
      )
      assert inverse_mellin_transform(
          -(2**s)
          * sqrt(pi)
          * gamma((s + 1) / 2)
          / (2 * s * gamma(-s / 2 + 1)),
          s,
          x,
          (-1, 0),
      ) == Si(x)
  
      assert mellin_transform(Ci(sqrt(x)), x, s) == (
          -(2 ** (2 * s - 1))
          * sqrt(pi)
          * gamma(s)
          / (s * gamma(-s + S.Half)),
          (0, 1),
          True,
      )
      assert inverse_mellin_transform(
          -(4**s)
          * sqrt(pi)
          * gamma(s)
          / (2 * s * gamma(-s + S.Half)),
          s,
          u,
          (0, 1),
      ).expand() == Ci(sqrt(u))
  
imports: from sympy.integrals.transforms import mellin_transform, inverse_mellin_transform, fourier_transform, inverse_fourier_transform, sine_transform, inverse_sine_transform, cosine_transform, inverse_cosine_transform, hankel_transform, inverse_hankel_transform, FourierTransform, SineTransform, CosineTransform, InverseFourierTransform, InverseSineTransform, InverseCosineTransform, IntegralTransformError
  from sympy.integrals.laplace import laplace_transform, inverse_laplace_transform
  from sympy.core.function import Function, expand_mul
  from sympy.core import EulerGamma
  from sympy.core.numbers import I, Rational, oo, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol, symbols
  from sympy.functions.combinatorial.factorials import factorial
  from sympy.functions.elementary.complexes import re, unpolarify
  from sympy.functions.elementary.exponential import exp, exp_polar, log
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.functions.elementary.trigonometric import atan, cos, sin, tan
  from sympy.functions.special.bessel import besseli, besselj, besselk, bessely
  from sympy.functions.special.delta_functions import Heaviside
  from sympy.functions.special.error_functions import erf, expint
  from sympy.functions.special.gamma_functions import gamma
  from sympy.functions.special.hyper import meijerg
  from sympy.simplify.gammasimp import gammasimp
  from sympy.simplify.hyperexpand import hyperexpand
  from sympy.simplify.trigsimp import trigsimp
  from sympy.testing.pytest import XFAIL, slow, skip, raises
  from sympy.abc import x, s, a, b, c, d
label_desc: Use image node_id 8 for calling a global function with example usage: test_expint() without return types