How to get the log file when running local AppEngine?

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appengine {
    downloadSdk = true
    httpPort = 8085
    appcfg {
        oauth2 = true
        email = appEmail
        passIn = true
          logs {
            severity = 0
            outputFile = file("LocalLogs.txt")
        }
          app {
            id = 'Groodle'
        }
    }
    endpoints {
        getClientLibsOnBuild = true
        getDiscoveryDocsOnBuild = true
    }
  //
  warDir = file("src/main/webapp")
      jvmFlags = ['-Xdebug', '-Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=9005']
}
  task runWar {
    dependsOn assemble, appengineRun
}

this is partial of my script, How does it manage to write to LocalLog.txt at my local?? I will trigger runWar at the first stage