```ruby
module Dropdown
  class Post
    attr_reader :source

    def initialize(source)
      @source = source
    end
  end
end
```

Include metadata parser in requires
user
```ruby
module Dropdown
  class Post
    attr_reader :source

    def title
      metadata[:title]
    end

    def initialize(source)
      @source = source
    end

    private

    def metadata
      unless @metadata
        @metadata = Dropdown::Parsers::MetadataParser.new(file)
        @metadata.parse
      end
      @metadata.headers
    end

    def file
      @file = File.new(@source, 'r') unless @file
      @file
    end
  end
end
```
assistant