how to add multiple variants to a product. by pauloHess

I follow the procedure below. It works when adding one variant but  doesn't work for more than one ... any ideas why? 

This is how I do it:
1- create an array called  
my_variants=Array.new

2- in a loop I add variants to it:

variant=ShopifyAPI::Variant.new(
  :option1              => "some option1",
  :option2              => "some option2",
  :sku                  => "AKJDKJ",
  :position             => 1,
  :price                => 10,   
  
)
        
my_variants<<variant 
OR
my_variants[i]=variant

3- add to product:
product = ShopifyAPI::Product.new(
  :title   =>"title1",
  ....
  :variants   => variants,
)
product.save