use sendgrid_thin::{Sendgrid, ContentType};

     fn main() {
        let mut sendgrid = Sendgrid::new("SENDGRID_API_KEY");

        // Required
        sendgrid
            .set_to_emails(&["[email protected]", "[email protected]"])
            .set_from_email("[email protected]")
            .set_subject("subject of email")
            .set_body("body of email");

        // Optional
        sendgrid
            .set_content_type(ContentType::Html)
            .set_send_at(1668281500)
            .set_cc_emails(&["[email protected]", "[email protected]"]);

        // Send the email
        match sendgrid.send() {
            Ok(message) => println!("{}", message),
            Err(err) => println!("Error sending email: {}", err),
        }
     }