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    cfg_net! {
        use crate::net::addr::{self, ToSocketAddrs};

        use std::io;
        use std::net::SocketAddr;

        /// Performs a DNS resolution.
        ///
        /// The returned iterator may not actually yield any values depending on the
        /// outcome of any resolution performed.
        ///
        /// This API is not intended to cover all DNS use cases. Anything beyond the
        /// basic use case should be done with a specialized library.
        ///
        /// # Examples
        ///
        /// To resolve a DNS entry:
        ///
        /// ```no_run
        /// use tokio::net;
        /// use std::io;
        ///
        /// #[tokio::main]
        /// async fn main() -> io::Result<()> {
        ///     for addr in net::lookup_host("localhost:3000").await? {
        ///         println!("socket address is {}", addr);
        ///     }
        ///
        ///     Ok(())
        /// }
        /// ```
        pub async fn lookup_host<T>(host: T) -> io::Result<impl Iterator<Item = SocketAddr>>
        where
            T: ToSocketAddrs
        {
            addr::to_socket_addrs(host).await
        }
    }