How to print the ParsedQuery (Or other AST types?) returned from `parse()`

[SteveLauC]

This is probably a really stupid question, I am trying to print the parsed AST out, but the ParsedQuery type does not have either Debug or Display implemented, and, it is a private type so you cannot check its documentation, a post I found shows that it was Debug:

use pg_query;

fn main() {
    let simple = "SELECT * FROM x";

    let medium = "SELECT COUNT(1) AS count, name section FROM t GROUP BY name LIMIT 10";

    let complex = "
SELECT
        country.country_name_eng,
        SUM(CASE WHEN talk.id IS NOT NULL THEN 1 ELSE 0 END) AS talks,
        AVG(ISNULL(DATEDIFF(SECOND, talk.start_time, talk.end_time),0)) AS avg_difference
FROM country
LEFT JOIN city ON city.country_id = country.id
LEFT JOIN customer ON city.id = customer.city_id
LEFT JOIN talk ON talk.customer_id = customer.id
GROUP BY
        country.id,
        country.country_name_eng
HAVING AVG(ISNULL(DATEDIFF(SECOND, talk.start_time, talk.end_time),0)) > (SELECT AVG(DATEDIFF(SECOND, talk.start_time, talk.end_time)) FROM talk)
ORDER BY talks DESC, country.id ASC;
";

    let simplebad = "SELECT * FROM GROUP BY age";

    let tests = vec![simple, medium, complex, simplebad];

    for test in tests {
        match pg_query::parse(test) {
            Ok(ast) => println!("AST: {:#?}", ast),
            Err(err) => println!("Error: {:#?}", err),
        }
    }
}

But the above code won't compile now because ParsedQuery is not Debug:

$ cargo r
   Compiling rust v0.1.0 (/Users/steve/Documents/workspace/rust)
error[E0277]: `pg_query::parse_result::ParseResult` doesn't implement `Debug`
  --> src/main.rs:30:47
   |
30 |             Ok(ast) => println!("AST: {:#?}", ast),
   |                                               ^^^ `pg_query::parse_result::ParseResult` cannot be formatted using `{:?}` because it doesn't implement `Debug`
   |
   = help: the trait `Debug` is not implemented for `pg_query::parse_result::ParseResult`
   = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)

For more information about this error, try `rustc --explain E0277`.
error: could not compile `rust` (bin "rust") due to 1 previous error