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: struct.rs
    path of file: ./repos/bevy/benches/benches/bevy_reflect
    
    the code of the file until where you have to start completion: use std::time::Duration;

use bevy_reflect::{DynamicStruct, GetField, Reflect, Struct};
use criterion::{
    black_box, criterion_group, criterion_main, BatchSize, 
    
fn dynamic_struct_get_field(criterion: &mut Criterion) {
    let mut group = criterion.benchmark_group("dynamic_struct_get");
    group.warm_up_time(WARM_UP_TIME);
    group.measurement_time(MEASUREMENT_TIME);

    for field_count in SIZES {
        group.throughput(Throughput::Elements(field_count as u64));
        group.bench_with_input(
            BenchmarkId::from_parameter(field_count),
            &field_count,
            |bencher, field_count| {
                let mut s = DynamicStruct::default();
                for i in 0..*field_count {
                    let field_name = format!("field_{}", i);
                    s.insert(&field_name, ());
                }

                let field = black_box("field_63");
                bencher.iter(|| {
                    black_box(s.get_field::<()>(field));
                });
            },
        );
    }
}