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: key_list.rb
    path of file: ./repos/roma/lib/roma/tools
    
    the code of the file until where you have to start completion: #!/usr/bin/env ruby
#
# usage:key_list storage-path [param_sleep(sec)]
#
module Roma
  module Storage
  end
  Storage::autoload(:TCStorage,'roma/storage/tokyocabinet')
  Storage::autoload(:DbmStorage,'roma/storage/dbm')
  Storage:
    
    def open_storage(path)
      unless File::directory?(path)
        STDERR.puts "#{path} does not found."
        return nil
      end

      # get a file extension
      ext = File::extname(Dir::glob("#{path}/0.*")[0])[1..-1]
      # count a number of divided files
      divnum = Dir::glob("#{path}/*.#{ext}").length

      st = new_storage(ext)
      st.divnum = divnum
      st.vn_list = []
      st.storage_path = path
      st.opendb
      st
    end