Represents a Processing Instruction.
If enabled, #PI pseudo-elements may appear as children
of any normal XML elements as well as within the pseudo-element #DOCUMENT.
Value:
The following Processing Instruction in an XML file:
<?php include("header.php");?>
#PI pseudo-element which, if it was a normal XML element, would look as the following:
<#PI target="php">include("header.php");</#PI>