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: common_spec.rb
    path of file: ./repos/siwapp-ror/spec/models
    
    the code of the file until where you have to start completion: require 'rails_helper'

RSpec.describe Common, :type => :model do

  def build_common(**kwargs)
    kwargs[:name] = "A Customer" unless kwargs.has_key? :name
    kwargs[:identification] = "123456789Z" unless kwargs.has_key? :identification
    kwarg
    
  def build_common(**kwargs)
    kwargs[:name] = "A Customer" unless kwargs.has_key? :name
    kwargs[:identification] = "123456789Z" unless kwargs.has_key? :identification
    kwargs[:series] = Series.new(value: "A") unless kwargs.has_key? :series

    common = Common.new(**kwargs, currency: "usd")
    common.set_amounts
    common
  end