I would like to create a vector of `HashMaps` in Rust. I have tried the following:

```
fn main() -> Vec<HashMap<String, String>> {
    let mut foo = HashMap::new();
    foo.insert("".to_string(), "".to_string());
    let f = Vec::new();
    f.push(foo);
    f
}

```

But I always get:

```none
error[E0580]: main function has wrong type
  --> src/main.rs:9:1
   |
9  | / fn main() -> Vec<HashMap<String, String>> {
10 | |     let mut foo = HashMap::new();
11 | |     foo.insert("".to_string(), "".to_string());
12 | |     let f = Vec::new();
13 | |     f.push(foo);
14 | |     f
15 | | }
   | |_^ expected (), found struct `std::vec::Vec`
   |
   = note: expected type `fn()`
              found type `fn() -> std::vec::Vec<std::collections::HashMap<std::string::String, std::string::String>>`

```