code: def _f_accel_decel(
      t, old_duration, new_duration, abruptness=1.0, soonness=1.0
  ):
      a = 1.0 + abruptness
  
      def _f(t):
          def f1(t):
              return (0.5) ** (1 - a) * (t**a)
  
          def f2(t):
              return 1 - f1(1 - t)
  
          return (t < 0.5) * f1(t) + (t >= 0.5) * f2(t)
  
      return old_duration * _f((t / new_duration) ** soonness)
  
label_desc: Use image node_id 1 for calling a global function with example usage: _f_accel_decel(t, old_duration, new_duration, abruptness, soonness) and returns: unknown, unknown, unknown, unknown