Method Underscores?

[Chris S.]

Is there a purpose for using trailing and leading double underscores for 
built-in method names? My impression was that underscores are supposed 
to imply some sort of pseudo-privatization, but would using 
myclass.len() instead of myclass.__len__() really cause Python 
considerable harm? As much as I adore Python, I have to admit, I find 
this to be one of the language's most "unPythonic" features and a key 
arguing point against Python. I've searched for a discussion on this 
topic in the groups archives, but found little. What are everyone's 
thoughts on this subject?