grape each entity in a single file

I want to have multiple classes inside grape entity file, this is the folder structure app/api/proj/api/v2/entities/committees.rb

module PROJ::API::V2::Entities
class Committee < Grape::Entity
expose :id

expose :name, :full_name, :email, :tag, :parent_id

expose :country do |entity, option|
  entity.parent.name if entity.parent.present?
end

# include Urls

private
  def self.namespace_path
    "committees"
  end
end

  class CommitteeWithSubcommittees < CommitteeBase
        # include ProfilePhoto 
        expose :suboffices, with: 'PROJ::API::V2::Entities::CommitteeBase'
      end

and inside the grape api

present @committees, with: PROJ::API::V2::Entities::Committee

is working. but if i present with

present @committees, with: PROJ::API::V2::Entities::CommitteeList

it is not working. But it works when i move it to a new file named committee_list.rb inside entities.