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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_jacobian_hessian_strategy(self):
 """ Figure out how to calculate the jacobian and hessian. Will return a tuple describing how best to calculate the jacobian and hessian, repectively. If None, it should be calculated using the available analytical method. :return: tuple of jacobian_method, hessian_method """

        if self.jacobian is not None and self.hessian is None:
            jacobian = None
            hessian = 'cs'
        elif self.jacobian is None and self.hessian is None:
            jacobian = 'cs'
            hessian = soBFGS(exception_strategy='damp_update')
        else:
            jacobian = None
            hessian = None
        return jacobian, hessian