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: json_compat.rb
    path of file: ./repos/chef/lib/chef
    
    the code of the file until where you have to start completion: #
# Author:: Tim Hinderliter (<tim@chef.io>)
# Copyright:: Copyright (c) Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License a
    
      def from_json(source, opts = {})
        obj = parse(source, opts)

        # JSON gem requires top level object to be a Hash or Array (otherwise
        # you get the "must contain two octets" error). Yajl doesn't impose the
        # same limitation. For compatibility, we re-impose this condition.
        unless obj.is_a?(Hash) || obj.is_a?(Array)
          raise Chef::Exceptions::JSON::ParseError, "Top level JSON object must be a Hash or Array. (actual: #{obj.class})"
        end

        obj
      end