You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: lib.rs
    path of file: ./repos/fluke/crates/fluke-hpack/src
    
    the code of the file until where you have to start completion: //! A module implementing HPACK functionality. Exposes a simple API for
//! performing the encoding and decoding of header sets, according to the
//! HPACK spec.

use std::collections::VecDeque;
use std::fmt;

use tracing::debug;

// Re-export the main HPACK API entry points.
pub use self::decoder::Decoder;
pub use self::encoder::Encoder;

pub mod decoder;
pub mod encoder;
pub mod huffman;

/// A struct representing the dynamic table that needs to be maintained by the
/// coder.
///
/// The dynamic table contains a number of recently used headers. The size of
/// the table is constrained to a certain number of octets. I
    
    pub fn find_header(&self, header: (&[u8], &[u8])) -> Option<(usize, bool)> {
        // Just does a simple scan of the entire table, searching for a header
        // that matches both the name and the value of the given header.
        // If no such header is found, then any one of the headers that had a
        // matching name is returned, with the appropriate return flag set.
        //
        // The tables are so small that it is unlikely that the linear scan
        // would be a major performance bottlneck. If it does prove to be,
        // though, a more efficient lookup/header representation method could
        // be devised.
        let mut matching_name: Option<usize> = None;
        for (i, h) in self.iter().enumerate() {
            if header.0 == h.0 {
                if header.1 == h.1 {
                    // Both name and value matched: returns it immediately
                    return Some((i + 1, true));
                }
                // If only the name was valid, we continue scanning, hoping to
                // find one where both the name and value match. We remember
                // this one, in case such a header isn't found after all.
                matching_name = Some(i + 1);
            }
        }

        // Finally, if there's no header with a matching name and value,
        // return one that matched only the name, if that *was* found.
        matching_name.map(|i| (i, false))
    }