Help me access Neo4j through Theo in macOS

I used CocoaPods to bring in Theo as a library.
(Theo is a Swift driver for Neo4j)
I made sample codes in Xcode to access Neo4j in Swift.
It was build successfully, but seems to fail accessing database.
Maybe the next line is wrong.

let client = try BoltClient(hostname: "localhost",
port: 7687,
username: "neo4j",
password: "<007>",
encrypted: true)

I use
macOS Mojave 10.14.6
Xcode 10.3
Theo 4.1.0