Python Threading not processed parallel

I'm intermidiate bee for python and would like to run the same class instances of few in parallel mode for fetching data and decision making for financial market. To proceed my idea, I run the following code to see how python works, it seems it works one complete run of first class instance and after second class instances, I would like to run this parallely, how can I...? Below is the some sample code for testing..

import threading
import time

class thr(object):

  def __init__(self, name):
     self.name = name
     self.x = 0

  def run(self):
     for i in list(range(10)):
         self.x +=1
         print("something {0} {1}".format(self.name, self.x))
         time.sleep(1)            

F = thr("First")
S = thr("Second")

threading.Thread(target=F.run())
threading.Thread(target=S.run())

and the results as below....

something First 1
something First 2
something First 3
something First 4
something First 5
something First 6
something First 7
something First 8
something First 9
something First 10
something Second 1
something Second 2
something Second 3
something Second 4
something Second 5
something Second 6
something Second 7
something Second 8
something Second 9
something Second 10
Out[27]: <Thread(Thread-25, initial)>