无法添加Google登录依赖

Question

# Uncomment the next line to define a global platform for your project
# platform :ios, '9.0'

target 'FacebookGoogleLogin' do
  # Comment the next line if you're not using Swift and don't want to use dynamic frameworks
  use_frameworks!
  pod 'Google/SignIn'
  pod 'FacebookCore'
  pod 'FacebookLogin'
  # Pods for FacebookGoogleLogin
end

这是我尝试安装Pod时的Pod文件bt。我遇到此错误：

  

“ [！]找不到Google/SignIn的规范”

我正在使用9.4 Xcode。