code: def test_color_func_scalar_val():
      # verify that eval_color_func returns a numpy array even when color_func
      # evaluates to a scalar value
      if not np:
          skip("numpy not installed.")
  
      x, y = symbols("x, y")
  
      s = Parametric2DLineSeries(
          cos(x),
          sin(x),
          (x, 0, 2 * pi),
          adaptive=False,
          n=10,
          color_func=lambda t: 1,
      )
      xx, yy, col = s.get_data()
      assert np.allclose(col, np.ones(xx.shape))
  
      s = Parametric3DLineSeries(
          cos(x),
          sin(x),
          x,
          (x, 0, 2 * pi),
          adaptive=False,
          n=10,
          color_func=lambda t: 1,
      )
      xx, yy, zz, col = s.get_data()
      assert np.allclose(col, np.ones(xx.shape))
  
      s = SurfaceOver2DRangeSeries(
          cos(x**2 + y**2),
          (x, -2, 2),
          (y, -2, 2),
          adaptive=False,
          n1=10,
          n2=10,
          color_func=lambda x: 1,
      )
      xx, yy, zz = s.get_data()
      assert np.allclose(s.eval_color_func(xx), np.ones(xx.shape))
  
      s = ParametricSurfaceSeries(
          1,
          x,
          y,
          (x, 0, 1),
          (y, 0, 1),
          adaptive=False,
          n1=10,
          n2=10,
          color_func=lambda u: 1,
      )
      xx, yy, zz, uu, vv = s.get_data()
      col = s.eval_color_func(xx, yy, zz, uu, vv)
      assert np.allclose(col, np.ones(xx.shape))
  
imports: from sympy import latex, exp, symbols, I, pi, sin, cos, tan, log, sqrt, re, im, arg, frac, Sum, S, Abs, lambdify, Function, dsolve, Eq, floor, Tuple
  from sympy.external import import_module
  from sympy.plotting.series import LineOver1DRangeSeries, Parametric2DLineSeries, Parametric3DLineSeries, SurfaceOver2DRangeSeries, ContourSeries, ParametricSurfaceSeries, ImplicitSeries, _set_discretization_points, List2DSeries
  from sympy.testing.pytest import raises, warns, XFAIL, skip, ignore_warnings
label_desc: Use image node_id 25 for calling a global function with example usage: test_color_func_scalar_val() without return types