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: errors.rb
    path of file: ./repos/pakyow/core/lib/pakyow
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require "json"

require_relative "error"

module Pakyow
  class EnvironmentError < Error
  end

  class ApplicationError < Error
  end

  class FormationError < Error
    class_state :messages, de
    
    def contextual_message
      release_channels = @context.release_channels.each_with_object(+"") { |channel, release_channels_message|
        release_channels_message << "  - #{channel.inspect}\n"
      }

      <<~MESSAGE
        Try using one of these available release channels:

        #{release_channels}
      MESSAGE
    end