i just recently replaced my brake master cylinder but now my brakes will not respond when pressed.

Did you use techstream or other device to run through the bleed procedure?

 

Also, was it new and ordered from a dealer who verified the part through your vin?

 

you'll need to fix the leak and bleed the brakes with a proper scanner

 

this guy says you don't need a scan tool watch

 

To JUST bleed the brake fluid, you wont' need any special tools.
But if you replace the master cylinder and/or pump, you NEED a special computer,
to do it correctly, and make sure the brakes work.

 

Agree. Bleeding a good Prius Master Cylinder is straightforward. However a replacement master cylinder needs all the passages inside bleed through a special Techstream process and it need its linear solenoid calibrated. There are few aftermarket very high end scanners capable of doing it and maybe the Autel AP200 depending who you believe.

 

You have a leak pure and simple. The proper Techstream process won't fix the leak.

I don't know about an opening that has no connection but if true it should not be leaking fluid.

It may require you to remove the part and carefully inspect each hydraulic connection. Also inspect the open "hole" for threads or plugs on your old master cylinder. It's possible plugs are not tight on your new part or simply missing.

Another resource can be pics on ebay of used parts. Sometimes salvage yards cut off lines leaving segments providing clues.

Example
10-15 TOYOTA PRIUS ANTI LOCK ABS BRAKE PUMP MASTER CYLINDER BOOSTER SET OEM | eBay