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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def function(self, x, y, amp, alpha, beta, center_x, center_y):
 """ returns Moffat profile """

        x_shift = x - center_x
        y_shift = y - center_y
        return amp * (1. + (x_shift**2+y_shift**2)/alpha**2)**(-beta)