Threading_Tutorial_02.py

import time
import threading

class PrintFactorial(threading.Thread):
    def __init__(self, n):
        super(PrintFactorial, self).__init__()      # call the original threading.Thread constructor
        self.n = n                                  # user-provided n value whose factorial value will be calculated in a new thread

    def run(self):
        """The 'run' method is a classmethod that will be run within a new thread.
        Because the return value is not stored, we are printing the value to stdout."""
        val = 1
        while self.n > 1:
            val *= self.n
            self.n -= 1
        print(val)

pf = PrintFactorial(33733)                          # creates a new instance of the above class
pf.start()                                          # executes the above run method in a new thread
print("Calculating... Awaiting ")                   # this occurs in the main thread
pf.join()                                           # blocks execution of the main thread until the run function is complete