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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def filename_unsafe(self):
 """The filename from the Content-Disposition header. If a location was passed at instanciation, the basename from that may be used as a fallback. Otherwise, this may be the None value. On safety: This property records the intent of the sender. You shouldn't use this sender-controlled value as a filesystem path, it can be insecure. Serving files with this filename can be dangerous as well, due to a certain browser using the part after the dot for mime-sniffing. Saving it to a database is fine by itself though. """


        if 'filename*' in self.assocs:
            return self.assocs['filename*'].string
        elif 'filename' in self.assocs:
            # XXX Reject non-ascii (parsed via qdtext) here?
            return self.assocs['filename']
        elif self.location is not None:
            return posixpath.basename(self.location_path.rstrip('/'))