code: def test_FourierSeries__operations():
      fo, fe, fp = _get_examples()
  
      fes = fe.scale(-1).shift(pi**2)
      assert fes.truncate() == 4 * cos(x) - cos(2 * x) + 2 * pi**2 / 3
  
      assert fp.shift(-pi / 2).truncate() == (
          2 * sin(x) + (2 * sin(3 * x) / 3) + (2 * sin(5 * x) / 5)
      )
  
      fos = fo.scale(3)
      assert fos.truncate() == 6 * sin(x) - 3 * sin(2 * x) + 2 * sin(
          3 * x
      )
  
      fx = fe.scalex(2).shiftx(1)
      assert (
          fx.truncate()
          == -4 * cos(2 * x + 2) + cos(4 * x + 4) + pi**2 / 3
      )
  
      fl = fe.scalex(3).shift(-pi).scalex(2).shiftx(1).scale(4)
      assert fl.truncate() == (
          -16 * cos(6 * x + 6)
          + 4 * cos(12 * x + 12)
          - 4 * pi
          + 4 * pi**2 / 3
      )
  
      raises(ValueError, lambda: fo.shift(x))
      raises(ValueError, lambda: fo.shiftx(sin(x)))
      raises(ValueError, lambda: fo.scale(x * y))
      raises(ValueError, lambda: fo.scalex(x**2))
  
imports: from sympy.core.add import Add
  from sympy.core.numbers import 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.piecewise import Piecewise
  from sympy.functions.elementary.trigonometric import cos, sin, sinc, tan
  from sympy.series.fourier import fourier_series
  from sympy.series.fourier import FourierSeries
  from sympy.testing.pytest import raises
  from functools import lru_cache
label_desc: Use image node_id 6 for calling a global function with example usage: test_FourierSeries__operations() without return types