Newbie: Why doesn't this work

[ct60 at aol.com]

Hi Python Community:

Despite my new-ness to Python  I have alreadhy been able to do some (I
think) amazing things.  It is a truly elegant and smart language.

Yet, I can not seem to get a handle on something simple.

I would like to make a class which has private varaiables fName and
lName.  It should have a property "name" which can get or set a name.
Something like as follows:

class Person:
    def __init__(self, fName="", lName=""):
        self.__fName = fName
        self.__lName = lName

    def __getattr__(self, attr):
        if attr == "name":
            return self.__fName + " " + self.__lName

    def __setattr__(self, attr, value):
        # this assumes that value is a tuple of first and last name
        if attr == "name":
            self.__fName, self.__lName = value


P = Person()

P.name = ("Joe", "Smith")

print P.name

This fails with the following note:

>>>
Traceback (most recent call last):
  File "C:\Python\testObject.py", line 20, in <module>
    print P.name
  File "C:\Python\testObject.py", line 8, in __getattr__
    return self.__fName + " " + self.__lName
TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'

I don't understand why this fails.  I thought perhaps I need to make
the __getattr__ function like this

    def __getattr__(self, attr):
        if attr == "name":
            return self.__fName + " " + self.__lName
        elif attr == "__fName":
            return self.__fName
        elif attr == "__lName":
            return self.__lName

But that still fails.

Can someone please tell me what I am doing wrong?

Thansk in advance,

Chris (ct60 at aol.com)