# File lib/thor/util.rb, line 139
    def self.namespace_to_thor_class_and_task(namespace, raise_if_nil=true)
      if namespace.include?(?:)
        pieces = namespace.split(":")
        task   = pieces.pop
        klass  = Thor::Util.find_by_namespace(pieces.join(":"))
      end

      unless klass
        klass, task = Thor::Util.find_by_namespace(namespace), nil
      end

      raise Error, "could not find Thor class or task '#{namespace}'" if raise_if_nil && klass.nil?
      return klass, task
    end