Add xml formatter in vimrc

.vimrc

@@ -338,5 +338,7 @@ endif
 
 " source $VIMRUNTIME/vimrc_example.vim
 " source $VIMRUNTIME/mswin.vim
-
+"
-
+" use FormatXML or `=` to format xml need python3 installed
+com! FormatXML :%!python3 -c "import xml.dom.minidom, sys; print(xml.dom.minidom.parse(sys.stdin).toprettyxml())"
+nnoremap = :FormatXML<Cr>