human
Solve the following python programming problem given the following code:
def test_len() : 
    def fun(x) : 
        assert (len (x) == 3) 
        return len (x) 
A = npr.randn (3, 2) 
    d_fun = (lambda x : to_scalar (grad (fun) (x))) 
    check_grads (fun, fun) 
    check_grads (d_fun, A) 

    
    

    Fix the buggy line: check_grads (fun, fun)
assistant
#Here is Python program to fix the buggy line: check_grads (fun, fun)
.

check_grads (fun, A)