set up rails

app/models/application_record.rb

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+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end

app/models/authorized_application.rb

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+class AuthorizedApplication < ApplicationRecord
+    belongs_to :user
+end

app/models/user.rb

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+class User < ApplicationRecord
+    # Include default devise modules. Others available are:
+    # :confirmable, :lockable, :timeoutable, :trackable and :omniauthable
+    devise :database_authenticatable, :registerable,
+         :recoverable, :rememberable, :validatable,
+         :trackable, :confirmable
+
+    has_many :authorized_applications, dependent: :destroy
+end