Added multiprocessing testing

mp_counter.py

@@ -0,0 +1,29 @@
+import time
+from multiprocessing import Process, Value, Lock
+
+class Counter(object):
+    def __init__(self, initval=0):
+        self.val = Value('i', initval)
+        self.lock = Lock()
+
+    def increment(self):
+        with self.lock:
+            self.val.value += 1
+
+    def value(self):
+        with self.lock:
+            return self.val.value
+
+def func(counter):
+    for i in range(50):
+        time.sleep(0.01)
+        counter.increment()
+
+if __name__ == '__main__':
+    counter = Counter(0)
+    procs = [Process(target=func, args=(counter,)) for i in range(10)]
+
+    for p in procs: p.start()
+    for p in procs: p.join()
+
+    print (counter.value())