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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 set_grads(params, params_with_grad):
 """ Copies gradients from param_with_grad to params :param params: dst parameters :param params_with_grad: src parameters """

        for param, param_w_grad in zip(params, params_with_grad):
            if param.grad is None:
                param.grad = torch.nn.Parameter(torch.empty_like(param))
            param.grad.data.copy_(param_w_grad.grad.data)