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: mod.rs
    path of file: ./repos/wezterm/wezterm-font/src/shaper
    
    the code of the file until where you have to start completion: use crate::parser::ParsedFont;
use crate::units::PixelLength;
use std::ops::Range;
use termwiz::cell::Presentation;
use termwiz::cellcluster::CellCluster;

pub mod harfbuzz;
pub use wezterm_bidi::Direction;

/// Holds information about a shaped glyph
#[derive(Clone, Debug, PartialEq)]
pub struct GlyphInfo {
   
    
    pub fn num_cells(&self, cluster_range: Range<usize>) -> u8 {
        let mut width = 0;
        let mut done_cells = vec![];

        for byte_idx in cluster_range {
            let cell_idx = self.cluster.byte_to_cell_idx(byte_idx);
            if done_cells.contains(&cell_idx) {
                continue;
            }
            done_cells.push(cell_idx);
            width += self.cluster.byte_to_cell_width(byte_idx);
        }
        width
    }