Lets you manage items in your keychain. Encodes and decodes the items as Data, and therefore requires that the types of items being added conform to Codable.
let keychainManager: KeychainManager = .standard
keychainManager.accessGroup = <app access_group>
try keychainManager.clear()
let value: SomeCodableType = try keychainManager.value(key: "key")
try keychainManager.save(someValue, key: "key", accessibility: kSecAttrAccessibleAfterFirstUnlock)