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    use crate::io::AsyncWrite;

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

    pin_project! {
        /// A future to write some of the buffer to an `AsyncWrite`.
        #[derive(Debug)]
        #[must_use = "futures do nothing unless you `.await` or poll them"]
        pub struct Write<'a, W: ?Sized> {
            writer: &'a mut W,
            buf: &'a [u8],
            // Make this future `!Unpin` for compatibility with async trait methods.
            #[pin]
            _pin: PhantomPinned,
        }
    }

    /// Tries to write some bytes from the given `buf` to the writer in an
    /// asynchronous manner, returning a future.
    pub(crate) fn write<'a, W>(writer: &'a mut W, buf: &'a [u8]) -> Write<'a, W>
    where
        W: AsyncWrite + Unpin + ?Sized,
    {
        Write {
            writer,
            buf,
            _pin: PhantomPinned,
        }
    }

    impl<W> Future for Write<'_, W>
    where
        W: AsyncWrite + Unpin + ?Sized,
    {
        type Output = io::Result<usize>;

        fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> {
            let me = self.project();
            Pin::new(&mut *me.writer).poll_write(cx, me.buf)
        }
    }