Why can't I use Go for the XML External Entities (XXE) lesson?

XXE or XML External Entity attacks rely on an XML parsers that understands and parses XML external entities. The Go XML parser, encode/xml, doesn't parse XML external entities and thusly isn't vulnerable to XXE exploits.

Other languages are supported, such as Java, Python, C#, etc. and you should be able to complete the lesson using another language.