Question: 
Write a function to extract all the pairs which are symmetric in the given tuple list.


Model's Code:
def extract_symmetric(lst):
    symmetric_pairs = set()
    seen = set()
    
    for a, b in lst:
        if (b, a) in seen:
            symmetric_pairs.add((a, b))
        seen.add((a, b))
    
    return symmetric_pairs



Sample Correct Code:
def extract_symmetric(test_list):
  temp = set(test_list) & {(b, a) for a, b in test_list}
  res = {(a, b) for a, b in temp if a < b}
  return (res) 


Asserts:
assert extract_symmetric([(6, 7), (2, 3), (7, 6), (9, 8), (10, 2), (8, 9)] ) == {(8, 9), (6, 7)}
assert extract_symmetric([(7, 8), (3, 4), (8, 7), (10, 9), (11, 3), (9, 10)] ) == {(9, 10), (7, 8)}
assert extract_symmetric([(8, 9), (4, 5), (9, 8), (11, 10), (12, 4), (10, 11)] ) == {(8, 9), (10, 11)}


Tests:
Test 1 of 3: FAIL: AssertionError()

Test 490 of 974: 361/490 (73.67346938775509%): failed