code: def test_expand_func():
      # evaluation at 1 of Gauss' hypergeometric function:
      from sympy.abc import a, b, c
      from sympy.core.function import expand_func
  
      a1, b1, c1 = randcplx(), randcplx(), randcplx() + 5
      assert expand_func(hyper([a, b], [c], 1)) == gamma(c) * gamma(
          -a - b + c
      ) / (gamma(-a + c) * gamma(-b + c))
      assert (
          abs(
              expand_func(hyper([a1, b1], [c1], 1)).n()
              - hyper([a1, b1], [c1], 1).n()
          )
          < 1e-10
      )
  
      # hyperexpand wrapper for hyper:
      assert expand_func(hyper([], [], z)) == exp(z)
      assert expand_func(hyper([1, 2, 3], [], z)) == hyper(
          [1, 2, 3], [], z
      )
      assert expand_func(meijerg([[1, 1], []], [[1], [0]], z)) == log(
          z + 1
      )
      assert expand_func(meijerg([[1, 1], []], [[], []], z)) == meijerg(
          [[1, 1], []], [[], []], z
      )
  
imports: from sympy.core.containers import Tuple
  from sympy.core.function import Derivative
  from sympy.core.numbers import I, Rational, oo, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import symbols
  from sympy.functions.elementary.exponential import exp, log
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.functions.elementary.trigonometric import cos
  from sympy.functions.special.gamma_functions import gamma
  from sympy.functions.special.hyper import appellf1, hyper, meijerg
  from sympy.series.order import O
  from sympy.abc import x, z, k
  from sympy.series.limits import limit
  from sympy.testing.pytest import raises, slow
  from sympy.core.random import random_complex_number, verify_numerically, test_derivative_numerically
label_desc: Use image node_id 3 for calling a global function with example usage: test_expand_func() without return types