```rust
use useful_macro::*;
//get argument and into Vec
//get input and into String let s = input!(); println!("{:?}",s);
//power of two f64 number let p = powf!(2.,2.); println!("{:?}",p);
//split a:&str by b:&str and collect into Vec
let s = splittovec!("aa.bb",".");
println!("{:?}",s);
// read .csv file and return Vec
// return sorted new Vec ,type can be Vec
// return sorted and deduped new Vec
// type can be Vec