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: istioctl.rb
    path of file: ./repos/homebrew-core/Formula/i
    
    the code of the file until where you have to start completion: class Istioctl < Formula
  desc "Istio configuration command-line utility"
  homepage "https://istio.io/"
  url "https://github.com/istio/istio/archive/refs/tags/1.20.3.tar.gz"
  sha256 "1e9d8cd5125372053587ce91034e963de71eb826d8
    
  def install
    ldflags = %W[
      -s -w
      -X istio.io/istio/pkg/version.buildVersion=#{version}
      -X istio.io/istio/pkg/version.buildGitRevision=#{tap.user}
      -X istio.io/istio/pkg/version.buildStatus=#{tap.user}
      -X istio.io/istio/pkg/version.buildTag=#{version}
      -X istio.io/istio/pkg/version.buildHub=docker.io/istio
    ]
    system "go", "build", *std_go_args(ldflags:), "./istioctl/cmd/istioctl"

    generate_completions_from_executable(bin/"istioctl", "completion")
    system bin/"istioctl", "collateral", "--man"
    man1.install Dir["*.1"]
  end