Function covid19db::dateutil::ymd_to_dateutc

pub fn ymd_to_dateutc(year: i32, month: u32, day: u32) -> Date<Utc>

Convert a year, month, day to a Date<Utc>

use covid19db::dateutil::*;
use chrono::prelude::*;

assert_eq!(ymd_to_dateutc(2015, 3, 14), Utc.ymd(2015, 3, 14));