human
Solve the following python programming problem given the following code:
def check_shape_mismatch(self, x_data) : 
    xp = cuda.get_array_module (self) 
    class DummyFunction (chainer.Function) : 
        label = 'dummy_function' 
        def forward(self, inputs) : 
            return (xp.array (1, np.float32),) 
def backward(self, inputs, grads) : 
            return (xp.array ([1, 2], np.float32),) 
x = chainer.Variable (x_data) 
    y = DummyFunction () (x) 
    with six.assertRaisesRegex (self, ValueError, 'dummy_function') : 
        y.backward () 

    
    

    Fix the buggy line: xp = cuda.get_array_module (self)
assistant
#Here is Python code to fix the buggy line: xp = cuda.

xp = cuda.get_array_module (x_data)