Shopify GraphQL admin api productCreate input object doesn't have variants

I am trying to create a shopify product as well as multiple variants all in the same productCreate mutation.

This is the query I have:

mutation CreateProductWithOptions($input: ProductInput!) {
  productCreate(input: $input) {
    userErrors {
      field
      message
    }
    product {
      id
      options {
        id
        name
        position
        values
        optionValues {
          id
          name
          hasVariants
        }
      }
      variants(first: 5) {
        nodes {
          id
          title
          selectedOptions {
            name
            value
          }
        }
      }
    }
  }
}

This is the productOptions:

[{"name":"colours","values":[{"name":"blue"},{"name":"green"}]},{"name":"sizes","values":[{"name":"Medium"},{"name":"Small"}]}]

And this is the variants:

[{"barcode":"C1AQ68VG","options":"colours: blue / sizes: Medium"},{"barcode":"6C7AS6KG","options":"colours: blue / sizes:
Small"},{"barcode":"UHWACOLQ","options":"colours: green / sizes: Medium"},{"barcode":"0P07QNKL","options":"colours: green / sizes: Small"}]

My input looks like this:

input: {
          title, // Product title
          productOptions, // Product options
          variants,
        },

But it didn't create successfully.

Is this completely wrong?

I saw this post on Shopify forum: https://community.shopify.com/c/graphql-basics-and/adding-multiple-product-variants-with-graphql/m-p/1340228

and thought it would work.

Can someone help me out?

I have tried the codes I posted but it didn't create shopify products with multiple variants successfully.