1use std::fmt;
 2
 3use thiserror::Error;
 4
 5#[derive(Error, Debug)]
 6pub struct PaymentRequiredError;
 7
 8impl fmt::Display for PaymentRequiredError {
 9    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
10        write!(
11            f,
12            "Payment required to use this language model. Please upgrade your account."
13        )
14    }
15}