How to set up fixture with an enum in a has-many-through realtion

I am testing a Rails application and I can't quite figure out how to set up my fixtures correctly.

I have organizations, memberships and agents:

Agent:

has_many :memberships
has_many :organizations, through: :memberships

Organization:

  has_many :memberships
  has_many :agents, through: :memberships

Membership:

  belongs_to :organization
  belongs_to :agent

  enum role: [:owner, :admin, :agent]

Now I'd like to set up my fixtures and this is what I have so far:

Agent:

SonGoku: 
  first_name: Son
  last_name: Goku
  email: gen@kidama.com

  current_organization_id: one

Organization

one:
  name: "Freezer AG"

Membership

mem: 
  agent_id: SonGoku
  organization_id: one
  role: <%= ???  %> ??1?? 

So my first question is: Is that ok so far? And my second question is: How can I implement the role correctly, which is an enum in that has_many_through relationship?

Thank you very much, any help is appreciated!

Best