Added handling for PI.
Added handling for PI.

JDReutt/parenscript,JackDanger/parenscript,JackDanger/parenscript,vsedach/Parenscript,VincentToups/parenscript,manuel/parenscript,3b/parenscript,JackDanger/parenscript,fredericksilva/Parenscript