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/json_api_client/lib/json_api_client
    
    the code of the file until where you have to start completion: require 'rack'

module JsonApiClient
  modul
    
      def initialize(env_or_uri, msg = nil)
        env = nil

        if env_or_uri.kind_of?(Faraday::Env)
          env = env_or_uri
          @uri = env[:url]
        else
          @uri = env_or_uri
        end