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: foreign_keys.rs
    path of file: ./repos/prisma-engines/schema-engine/sql-migration-tests/tests/migrations
    
    the code of the file until where you have to start completion: use sql_migration_tests::test_api::*;
use sql_schema_describer::ForeignKeyAction;

#[test_connector]
fn foreign_keys_of_inline_one_to_one_relations_have_a_unique_constraint(api: TestApi) {
    let dm = r#"
        model Cat {
            id Int   @id
           
    
fn foreign_keys_can_be_added_on_existing_columns(api: TestApi) -> TestResult {
    let dm1 = r#"
        model User {
            id Int @id
            email String @unique
        }

        model Account {
            id Int @id
            user_email String
        }
    "#;

    api.schema_push_w_datasource(dm1).send().assert_green();

    api.assert_schema()
        // There should be no foreign keys yet.
        .assert_table("Account", |table| table.assert_foreign_keys_count(0));

    let dm2 = r#"
        model User {
            id    Int @id
            email String @unique
            a     Account[]
        }

        model Account {
            id Int @id
            user_email String
            user User @relation(fields: [user_email], references: [email])
        }
    "#;

    api.schema_push_w_datasource(dm2).send().assert_green();

    api.assert_schema().assert_table("Account", |table| {
        table
            .assert_foreign_keys_count(1)
            .assert_fk_on_columns(&["user_email"], |fk| fk.assert_references("User", &["email"]))
    });
}