def extract_even(test_tuple):
  def even_ele(test_tuple, even_fnc): 
  	res = tuple() 
  	for ele in test_tuple: 
  		if isinstance(ele, tuple): 
  			res += (even_ele(ele, even_fnc), ) 
  		elif even_fnc(ele): 
  			res += (ele, ) 
  	return res 
  
  res = even_ele(test_tuple, lambda x: x % 2 == 0)
  return (res) 
def extract_even(test_tuple):
  def even_ele(test_tuple, even_fnc): 
  	res = tuple() 
  	for ele in test_tuple: 
  		if isinstance(ele, tuple): 
  			res -= (even_ele(ele, even_fnc), ) 
  		elif even_fnc(ele): 
  			res += (ele, ) 
  	return res 
  
  res = even_ele(test_tuple, lambda x: x % 2 == 0)
  return (res) 