in _plugins/kramdown-with-pygments/kramdown_pygments.rb [39:53]
def convert_codespan(el, indent)
attr = el.attr.dup
lang = extract_code_language!(attr) || @options[:kramdown_default_lang]
code = pygmentize(el.value, lang)
if lang
attr['class'] = "highlight"
if attr.has_key?('class')
attr['class'] += " language-#{lang}"
else
attr['class'] = "language-#{lang}"
end
end
"<code#{html_attributes(attr)}>#{code}</code>"
end