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    use crate::future::maybe_done::{maybe_done, MaybeDone};

    use pin_project_lite::pin_project;
    use std::future::Future;
    use std::pin::Pin;
    use std::task::{Context, Poll};

    pub(crate) fn try_join3<T1, F1, T2, F2, T3, F3, E>(
        future1: F1,
        future2: F2,
        future3: F3,
    ) -> TryJoin3<F1, F2, F3>
    where
        F1: Future<Output = Result<T1, E>>,
        F2: Future<Output = Result<T2, E>>,
        F3: Future<Output = Result<T3, E>>,
    {
        TryJoin3 {
            future1: maybe_done(future1),
            future2: maybe_done(future2),
            future3: maybe_done(future3),
        }
    }

    pin_project! {
        pub(crate) struct TryJoin3<F1, F2, F3>
        where
            F1: Future,
            F2: Future,
            F3: Future,
        {
            #[pin]
            future1: MaybeDone<F1>,
            #[pin]
            future2: MaybeDone<F2>,
            #[pin]
            future3: MaybeDone<F3>,
        }
    }

    impl<T1, F1, T2, F2, T3, F3, E> Future for TryJoin3<F1, F2, F3>
    where
        F1: Future<Output = Result<T1, E>>,
        F2: Future<Output = Result<T2, E>>,
        F3: Future<Output = Result<T3, E>>,
    {
        type Output = Result<(T1, T2, T3), E>;

        fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
            let mut all_done = true;

            let mut me = self.project();

            if me.future1.as_mut().poll(cx).is_pending() {
                all_done = false;
            } else if me.future1.as_mut().output_mut().unwrap().is_err() {
                return Poll::Ready(Err(me.future1.take_output().unwrap().err().unwrap()));
            }

            if me.future2.as_mut().poll(cx).is_pending() {
                all_done = false;
            } else if me.future2.as_mut().output_mut().unwrap().is_err() {
                return Poll::Ready(Err(me.future2.take_output().unwrap().err().unwrap()));
            }

            if me.future3.as_mut().poll(cx).is_pending() {
                all_done = false;
            } else if me.future3.as_mut().output_mut().unwrap().is_err() {
                return Poll::Ready(Err(me.future3.take_output().unwrap().err().unwrap()));
            }

            if all_done {
                Poll::Ready(Ok((
                    me.future1.take_output().unwrap().ok().unwrap(),
                    me.future2.take_output().unwrap().ok().unwrap(),
                    me.future3.take_output().unwrap().ok().unwrap(),
                )))
            } else {
                Poll::Pending
            }
        }
    }