thread module provides an easy way for parallel execution of your functions in Python:

def a_function(args):
import thread
lock1=thread.allocate_lock()
lock2.acquire()
thread.start_new_thread(function1, (someargs, lock1))
lock2=thread.allocate_lock()
lock2.acquire()
thread.start_new_thread(function1, (someargs, lock2))
lock1.acquire()
lock2.acquire()
print 'Both threads finished'
function2(someargs)