reading large xml file: go encoding/xml is twice as slow as python lxml

I was considering to adapt go for my future projects for performance reason but there is a big surprise: go's running time is 13.974427s while pythons elapsed time is just 6.593028783798218s Less then a half!

The XML file size is over 300 MB. Here is the pythons's code:

from lxml import objectify
import time

most = time.time()

root = objectify.parse(open(r"c:\temp\myfile.xml", 'rb')).getroot()

if hasattr(root, 'BaseData'):
    if hasattr(root.BaseData, 'SzTTs'):
        total_records = 0
        for sztt in root.BaseData.SzTTs.sztt:
            total_records += 1
print("total_records", total_records)
print("Time elapsed: ", time.time()-most)

and here is the simplified go code:

package main

// An example streaming XML parser.

import (
    "encoding/xml"
    "fmt"
    "io"
    "os"
    "time"
)

var inputFile = "c:\\temp\\myfile.xml"

type SzTTs struct {
    Sztt []sztt
}

type sztt struct {
}

func main() {
    xmlFile, err := os.Open(inputFile)
    if err != nil {
        fmt.Println("Error opening file:", err)
        return
    }
    defer xmlFile.Close()

    d := xml.NewDecoder(xmlFile)
    total1 := 0
    total2 := 0
    start := time.Now()
    for {
        // Read tokens from the XML document in a stream.
        t, err := d.Token()
        // If we are at the end of the file, we are done
        if t == nil || err == io.EOF {
            fmt.Println("The end")
            break
        } else if err != nil {
            log.Fatalf("Error decoding token: %s", err)
        }

        // Inspect the type of the token just read.
        switch se := t.(type) {
        case xml.StartElement:

            if se.Name.Local == "SzTTs" {
                var p SzTTs
                // decode a whole chunk of following XML into the
                // variable p which is a Page (se above)
                if err = d.DecodeElement(&p, &se); err != nil {
                    log.Fatalf("Error decoding item: %s", err)
                }
                for i := range p.Sztt {
                    total1 = i
                }
            }
        default:
        }
    }

    fmt.Printf("Total sztt: %d \n", total1)
    fmt.Printf("Elapsed time %s", time.Since(start))
}

Why is this big difference?