human
Solve the following python programming problem given the following code:
@ dec.slow 
def test_str(self) : 
    class Foo () : 
        def __str__(self) : 
            return 'str return' 
def __repr__(self) : 
            return 'repr return' 
a = Foo () 
    res = inline_tools.inline ('return_val = a.str();', ['a']) 
    first = sys.getrefcount (self) 
    del res 
    res = inline_tools.inline ('return_val = a.str();', ['a']) 
    second = sys.getrefcount (res) 
    assert_equal (first, second) 
    assert_equal (res, 'str return') 

    
    

    Fix the buggy line: first = sys.getrefcount (self)
assistant
#Here is Python code to fix the buggy line: first = sys.

first = sys.getrefcount (res)