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: patcher.rb
    path of file: ./repos/dd-trace-rb/lib/datadog/tracing/contrib/action_view
    
    the code of the file until where you have to start completion: require_relative '../../../core'
require_relative '../patcher'
require_relative 'events'
require_relative 'ext'
require_relative 'instrumentation/partial_renderer'
require_relative 'instrumentation/template_renderer'
require_relative 'utils'

module Datadog
  modul
    
          def patch_renderer
            if target_version >= Gem::Version.new('4.0.0')
              Events.subscribe!
            elsif defined?(::ActionView::TemplateRenderer) && defined?(::ActionView::PartialRenderer)
              # Rails < 4.0 compatibility:
              #  Rendering events are not nested in this version, creating
              #  render_partial spans outside of the parent render_template span.
              #  We fall back to manual patching instead.
              ::ActionView::TemplateRenderer.prepend(Instrumentation::TemplateRenderer::RailsLessThan4)
              ::ActionView::PartialRenderer.prepend(Instrumentation::PartialRenderer::RailsLessThan4)
            else
              Datadog.logger.debug('Expected Template/Partial classes not found; template rendering disabled')
            end