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    use super::{Bytes, BytesMut};
    use alloc::string::String;
    use alloc::vec::Vec;
    use core::{cmp, fmt};
    use serde::{de, Deserialize, Deserializer, Serialize, Serializer};

    macro_rules! serde_impl {
        ($ty:ident, $visitor_ty:ident, $from_slice:ident, $from_vec:ident) => {
            impl Serialize for $ty {
                #[inline]
                fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
                where
                    S: Serializer,
                {
                    serializer.serialize_bytes(&self)
                }
            }

            struct $visitor_ty;

            impl<'de> de::Visitor<'de> for $visitor_ty {
                type Value = $ty;

                fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
                    formatter.write_str("byte array")
                }

                #[inline]
                fn visit_seq<V>(self, mut seq: V) -> Result<Self::Value, V::Error>
                where
                    V: de::SeqAccess<'de>,
                {
                    let len = cmp::min(seq.size_hint().unwrap_or(0), 4096);
                    let mut values: Vec<u8> = Vec::with_capacity(len);

                    while let Some(value) = seq.next_element()? {
                        values.push(value);
                    }

                    Ok($ty::$from_vec(values))
                }

                #[inline]
                fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
                where
                    E: de::Error,
                {
                    Ok($ty::$from_slice(v))
                }

                #[inline]
                fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
                where
                    E: de::Error,
                {
                    Ok($ty::$from_vec(v))
                }

                #[inline]
                fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
                where
                    E: de::Error,
                {
                    Ok($ty::$from_slice(v.as_bytes()))
                }

                #[inline]
                fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
                where
                    E: de::Error,
                {
                    Ok($ty::$from_vec(v.into_bytes()))
                }
            }

            impl<'de> Deserialize<'de> for $ty {
                #[inline]
                fn deserialize<D>(deserializer: D) -> Result<$ty, D::Error>
                where
                    D: Deserializer<'de>,
                {
                    deserializer.deserialize_byte_buf($visitor_ty)
                }
            }
        };
    }

    serde_impl!(Bytes, BytesVisitor, copy_from_slice, from);
    serde_impl!(BytesMut, BytesMutVisitor, from, from_vec);