perl数组中元素匹配的问题（已解决）

'''
Created on Jul 14, 2011

@author: bells
'''
__metaclass__ = type
class MyClass:
def smeth():
print 'This is s static method'
smeth = staticmethod(smeth)

def cmeth(cls):
print 'This is a class method', cls
cmeth = classmethod(cmeth)

print MyClass.cmeth()
print MyClass.smeth()

源代码见上面 在pydev中运行
输出如下：
This is a class method <class '__main__.MyClass'>
None
This is s static method
None

其中不能理解为什么会输出两个None ??麻烦解释下??