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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 init_prior(self, R):
 """initialize prior for the subject Returns ------- TFA Returns the instance itself. """

        centers, widths = self.init_centers_widths(R)
        # update prior
        prior = np.zeros(self.K * (self.n_dim + 1))
        self.set_centers(prior, centers)
        self.set_widths(prior, widths)
        self.set_prior(prior)
        return self