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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 _get_proposed_values(self):
 """ Method to perform time splitting using leapfrog """

        # Take half step in time for updating momentum
        momentum_bar = self.momentum + 0.5 * self.stepsize * self.grad_log_position

        # Take full step in time for updating position position
        position_bar = self.position + self.stepsize * momentum_bar

        grad_log, _ = self.grad_log_pdf(position_bar, self.model).get_gradient_log_pdf()

        # Take remaining half step in time for updating momentum
        momentum_bar = momentum_bar + 0.5 * self.stepsize * grad_log

        return position_bar, momentum_bar, grad_log