'Tells us if an addon is signed.'

def is_signed(self):

    finds = []
    for info in self.info:
        match = SIGNED_RE.match(info.filename)
        if match:
            (name, ext) = match.groups()
            if ((name, {'rsa': 'sf', 'sf': 'rsa'}[ext]) in finds):
                return True
            finds.append((name, ext))
