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
dataset/ETHPy150Open kayhayen/Nuitka/nuitka/build/inline_copy/lib/scons-2.3.2/SCons/Subst.py/SpecialAttrWrapper.__init__