def __init__(self, lstr, for_signature=None):
        """The for_signature parameter, if supplied, will be the
        canonical string we return from for_signature().  Else
        we will simply return lstr."""
        self.lstr = lstr
        if for_signature:
            self.forsig = for_signature
        else:
            self.forsig = lstr
def __init__ ( self , lstr , for_signature = None ) : self . lstr = lstr if for_signature : self . forsig = for_signature else : self . forsig = lstr
The for_signature parameter, if supplied, will be the
        canonical string we return from for_signature().  Else
        we will simply return lstr.