Sometimes, we set up a default input value to call our function more efficiently. Here, we use the dir2() function, which we created in the last section as an example. If the most frequently called directory is in C: Python32, we could set it as our default input value. This means after we activate this function and issue >>>dir2(), the contents under this directory will be displayed automatically, as shown in the following code:

def dir2(path="c:\python32"):
    from os import listdir
    print(listdir(path))    

By the way, when a function needs inputs and there are no default input values, we would receive an error message when we don't have input values.