///
/// This trait is sealed and cannot be implemented for types outside of
/// `anyhow`.

pub trait Context<T, E> {

pub trait Context<T, E>: private::Sealed {

}
mod private {
    use crate::Error;
    use std::error::Error as StdError;
    pub trait Sealed {}
    impl<T, E> Sealed for Result<T, E> where E: StdError + Send + Sync + 'static {}
    impl<T> Sealed for Result<T, Error> {}
    impl<T> Sealed for Option<T> {}