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: basic.rs
    path of file: ./repos/calamine/benches
    
    the code of the file until where you have to start completion: #![feature(test)]

extern crate test;

use calamine::{open_workbook, Ods, Reader, Xls, Xlsb, Xlsx};
use std::fs::File;
use std::io::BufReader;
use test::Bencher;

fn count<R: Reader
    
fn bench_xlsx_cells_reader(b: &mut Bencher) {
    fn count<R: Reader<BufReader<File>>>(path: &str) -> usize {
        let path = format!("{}/{}", env!("CARGO_MANIFEST_DIR"), path);
        let mut excel: Xlsx<_> = open_workbook(&path).expect("cannot open excel file");

        let sheets = excel.sheet_names().to_owned();
        let mut count = 0;
        for s in sheets {
            let mut cells_reader = excel.worksheet_cells_reader(&s).unwrap();
            while let Some(_) = cells_reader.next_cell().unwrap() {
                count += 1;
            }
        }
        count
    }
    b.iter(|| count::<Xlsx<_>>("tests/issues.xlsx"));
}