human
Solve the following python programming problem given the following code:
def test_mutabledisposable_replacebeforedispose() : 
    disp1 = [False] 
    disp2 = [False] 
    m = SerialDisposable () 
    def action1() : 
        disp1 [0] = True 
d1 = Disposable (d1) 
    m.disposable = d1 
    assert (d1 == m.disposable) 
    assert (not disp1 [0]) 
    def action2() : 
        disp2 [0] = True 
d2 = Disposable (action2) 
    m.disposable = d2 
    assert (d2 == m.disposable) 
    assert disp1 [0] 
    assert (not disp2 [0]) 

    
    

    Fix the buggy line: d1 = Disposable (d1)
assistant
#Here is Python program to fix the buggy line: d1 = Disposable (d1)
.

d1 = Disposable (def action1()