pub fn version_string() -> String {
let version = env!("CARGO_PKG_VERSION");
let git_hash = env!("OCPPSIM_GIT_HASH");
let build_date = env!("OCPPSIM_BUILD_DATE");
let target = env!("OCPPSIM_TARGET");
format!("{version} ({git_hash} {build_date} {target})")
}