.rb

# Fun fact: Rails relation methods have an argument which doesn't appear to do anything 

task = Task.first
task.created_by_user
# a user
task.created_by_user(true)
task.created_by_user('anything here')
task.created_by_user({some: 'irrelevant', attributes: true})
# no errors, user is returned.
task.created_by_user(1,2)
# Wrong number of arguments error