You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: byoid_mongo.rs
    path of file: ./repos/prisma-engines/query-engine/connector-test-kit-rs/query-engine-tests/tests/writes/ids
    
    the code of the file until where you have to start completion: use query_engine_tests::*;

// "bring_your_own_id_mongo"
#[test_suite(only(MongoDb))]
mod byoi_mongo {
    use indoc::indoc;
    use query_engine_tests::{assert_error, run_query, Runner};

    fn schema_1() -> String {
        let schema = indoc! {
            r#"model Parent {
              #id(id, String, @id, @default(cuid()))
              p        String  @unique
              childOpt Child?  @relation(fields: [childId], references: [id])
              childId  String? @unique
          }

         
    
    async fn nested_create_return_item_woi_1(runner: Runner) -> TestResult<()> {
        insta::assert_snapshot!(
          run_query!(&runner, r#"mutation {
            createOneParent(data: {p: "Parent", id: "5c88f558dee5fb6fe357c7a9", childOpt:{create:{c:"Child", id: "5c88f558dee5fb6fe357c7a5"}}}){p, id, childOpt { c, id} }
          }"#),
          @r###"{"data":{"createOneParent":{"p":"Parent","id":"5c88f558dee5fb6fe357c7a9","childOpt":{"c":"Child","id":"5c88f558dee5fb6fe357c7a5"}}}}"###
        );

        assert_error!(
            &runner,
            r#"mutation {
              createOneParent(data: {p: "Parent 2", id: "5c88f558dee5fb6fe357c7a3", childOpt:{create:{c:"Child 2", id: "5c88f558dee5fb6fe357c7a5"}}}){p, id, childOpt { c, id} }
            }"#,
            2002,
            "Unique constraint failed on the constraint: `_id_`"
        );

        Ok(())
    }