code: def test_f1a2():
      # issue 3509:
      assert limit(((x - 1) / (x + 1)) ** x, x, oo) == exp(-2)
  
imports: from sympy.core.numbers import Rational, oo, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol
  from sympy.functions.elementary.exponential import exp, log
  from sympy.functions.elementary.miscellaneous import root, sqrt
  from sympy.functions.elementary.trigonometric import asin, cos, sin, tan
  from sympy.polys.rationaltools import together
  from sympy.series.limits import limit
label_desc: Use image node_id 15 for calling a global function with example usage: test_f1a2() without return types