eval of a private attribute

[J.Jacob]

How to get to a variable hidden behind two underscores...
The get() method in this class returns a public or 'private' attribute
or None if no such attribute.

class CObsFile:
    def __init__(self):
        self.__user = "~briner/big/usr.rdb"
        self.public_user = "thatsme_public"
    def get(self, var):
        if hasattr(self, var):
            tobeEval = var
            p = getattr(self, var)
        else:
            try:
                tobeEval = 'self._CObsFile__'+var
                p = eval(tobeEval)
            except AttributeError:
                p = None
        return p

p = CObsFile()
print p.get('public_user')	# get a public attribute
print p.get('user')		# get a 'private' attribute
print p.get('nosuchuser')	# get a nonexisting attribute