old_contents: def fun1(val=5):
      print(5)
  
  fun1()
  fun1(10)
  
  def fun2(p1, p2=100, p3="foo"):
      print(p1, p2, p3)
  
  fun2(1)
  fun2(1, None)
  fun2(0, "bar", 200)
  try:
      fun2()
  except TypeError:
      print("TypeError")
  try:
      fun2(1, 2, 3, 4)
  except TypeError:
      print("TypeError")
  
new_contents: def fun1(val=5):
      print(val)
  
  fun1()
  fun1(10)
  
  def fun2(p1, p2=100, p3="foo"):
      print(p1, p2, p3)
  
  fun2(1)
  fun2(1, None)
  fun2(0, "bar", 200)
  try:
      fun2()
  except TypeError:
      print("TypeError")
  try:
      fun2(1, 2, 3, 4)
  except TypeError:
      print("TypeError")
  
subject: Fix default arg test.