code: def test_to_hyper():
      x = symbols("x")
      R, Dx = DifferentialOperators(QQ.old_poly_ring(x), "Dx")
      p = HolonomicFunction(Dx - 2, x, 0, [3]).to_hyper()
      q = 3 * hyper([], [], 2 * x)
      assert p == q
      p = hyperexpand(
          HolonomicFunction((1 + x) * Dx - 3, x, 0, [2]).to_hyper()
      ).expand()
      q = 2 * x**3 + 6 * x**2 + 6 * x + 2
      assert p == q
      p = HolonomicFunction(
          (1 + x) * Dx**2 + Dx, x, 0, [0, 1]
      ).to_hyper()
      q = -(x**2) * hyper((2, 2, 1), (3, 2), -x) / 2 + x
      assert p == q
      p = HolonomicFunction(
          2 * x * Dx + Dx**2, x, 0, [0, 2 / sqrt(pi)]
      ).to_hyper()
      q = (
          2
          * x
          * hyper((S.Half,), (Rational(3, 2),), -(x**2))
          / sqrt(pi)
      )
      assert p == q
      p = hyperexpand(
          HolonomicFunction(
              2 * x * Dx + Dx**2, x, 0, [1, -2 / sqrt(pi)]
          ).to_hyper()
      )
      q = erfc(x)
      assert p.rewrite(erfc) == q
      p = hyperexpand(
          HolonomicFunction(
              (x**2 - 1) + x * Dx + x**2 * Dx**2,
              x,
              0,
              [0, S.Half],
          ).to_hyper()
      )
      q = besselj(1, x)
      assert p == q
      p = hyperexpand(
          HolonomicFunction(
              x * Dx**2 + Dx + x, x, 0, [1, 0]
          ).to_hyper()
      )
      q = besselj(0, x)
      assert p == q
  
imports: from sympy.holonomic import DifferentialOperator, HolonomicFunction, DifferentialOperators, from_hyper, from_meijerg, expr_to_holonomic
  from sympy.holonomic.recurrence import RecurrenceOperators, HolonomicSequence
  from sympy.core import EulerGamma
  from sympy.core.numbers import I, Rational, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol, symbols
  from sympy.functions.elementary.exponential import exp, log
  from sympy.functions.elementary.hyperbolic import asinh, cosh
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.functions.elementary.trigonometric import cos, sin
  from sympy.functions.special.bessel import besselj
  from sympy.functions.special.beta_functions import beta
  from sympy.functions.special.error_functions import Ci, Si, erf, erfc
  from sympy.functions.special.gamma_functions import gamma
  from sympy.functions.special.hyper import hyper, meijerg
  from sympy.printing.str import sstr
  from sympy.series.order import O
  from sympy.simplify.hyperexpand import hyperexpand
  from sympy.polys.domains.integerring import ZZ
  from sympy.polys.domains.rationalfield import QQ
  from sympy.polys.domains.realfield import RR
label_desc: Use image node_id 15 for calling a global function with example usage: test_to_hyper() without return types