code: def test_powm1():
      args = x, y = map(Symbol, "xy")
  
      expr1 = x**y - 1
      opt1 = optimize(expr1, [powm1_opt])
      assert opt1 == powm1(x, y)
      for arg in args:
          assert expr1.diff(arg) == opt1.diff(arg)
      if scipy and tuple(
          map(int, scipy.version.version.split(".")[:3])
      ) >= (1, 10, 0):
          subs1_a = {
              x: Rational(*(1.0 + 1e-13).as_integer_ratio()),
              y: pi,
          }
          ref1_f64_a = 3.139081648208105e-13
          _check_num_lambdify(
              expr1,
              opt1,
              subs1_a,
              ref1_f64_a,
              lambdify_kw={"modules": "scipy"},
              poorness=10**11,
          )
  
          subs1_b = {x: pi, y: Rational(*(1e-10).as_integer_ratio())}
          ref1_f64_b = 1.1447298859149205e-10
          _check_num_lambdify(
              expr1,
              opt1,
              subs1_b,
              ref1_f64_b,
              lambdify_kw={"modules": "scipy"},
              poorness=10**9,
          )
  
imports: import tempfile
  from sympy.core.numbers import pi, Rational
  from sympy.core.power import Pow
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol
  from sympy.functions.elementary.complexes import Abs
  from sympy.functions.elementary.exponential import exp, log
  from sympy.functions.elementary.trigonometric import cos, sin, sinc
  from sympy.matrices.expressions.matexpr import MatrixSymbol
  from sympy.assumptions import assuming, Q
  from sympy.external import import_module
  from sympy.printing.codeprinter import ccode
  from sympy.codegen.matrix_nodes import MatrixSolve
  from sympy.codegen.cfunctions import log2, exp2, expm1, log1p
  from sympy.codegen.numpy_nodes import logaddexp, logaddexp2
  from sympy.codegen.scipy_nodes import cosm1, powm1
  from sympy.codegen.rewriting import optimize, cosm1_opt, log2_opt, exp2_opt, expm1_opt, log1p_opt, powm1_opt, optims_c99, create_expand_pow_optimization, matinv_opt, logaddexp_opt, logaddexp2_opt, optims_numpy, optims_scipy, sinc_opts, FuncMinusOneOptim
  from sympy.testing.pytest import XFAIL, skip
  from sympy.utilities import lambdify
  from sympy.utilities._compilation import compile_link_import_strings, has_c
  from sympy.utilities._compilation.util import may_xfail
label_desc: Use image node_id 10 for calling a global function with example usage: test_powm1() without return types