John 17:9 & Calvinism

In John 17:9 Jesus said, “I do not pray for the world.” Calvinism teaches that God predestined some to be either saved or lost before birth. Predestination in Calvinism removes any free will. Calvinists quote this verse as proof that God does not love, did not die for, nor prays for the world, but only for those given to Him. This contradicts verse 21, “that the world may believe that You sent Me” and verse 23, “that the world may know that You have sent Me.” As “Savior of the world” (1 John 4:14), it was Jesus normal practice to pray for the world, just not in this instance.