{
  "headers" : {
    "Authorization" : "Bearer the api key",
    "content-type" : "application/json",
    "X-Client-Build-Version" : "12345",
    "X-Client-Bundle-ID" : "com.apple.dt.xctest.tool",
    "X-Client-Version" : "17.0.0",
    "X-Is-Debug-Build" : "true",
    "X-Is-Sandbox" : "false",
    "X-Observer-Mode-Enabled" : "false",
    "X-Platform" : "iOS",
    "X-Platform-Device" : "arm64",
    "X-Platform-Flavor" : "Unity",
    "X-Platform-Flavor-Version" : "2.3.3",
    "X-Platform-Version" : "Version 17.0.0 (Build 21A342)",
    "X-Preferred-Locales" : "en_US",
    "X-Retry-Count" : "0",
    "X-Storefront" : "USA",
    "X-StoreKit-Version" : "2",
    "X-StoreKit2-Enabled" : "true",
    "X-Version" : "4.0.0"
  },
  "request" : {
    "body" : {
      "attributes" : {
        "a key" : {
          "updated_at_ms" : 1678307200000,
          "value" : "a value"
        },
        "another key" : {
          "updated_at_ms" : 1678307200000,
          "value" : "another value"
        }
      }
    },
    "method" : "POST",
    "url" : "https://api.revenuecat.com/v1/subscribers/abc123/attributes"
  }
}