Update Readme.md

Readme.md

@@ -10,10 +10,11 @@ Do a parallel map(func, tasks) with numProc processes
 ## How to use
 
 ```python
+from pyParallelRunAndWrite import parallelRunAndWrite as prw
+# The following dependencies are only useful for testFunc
 import os
 from time import sleep
 from random import randint
-from pyParallelRunAndWrite import parallelRunAndWrite as prw
 
 def testFunc(arg):
     ret=str(arg)+str(os.getpid())