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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 read_blacklist (self):
 """ Read a previously stored blacklist from file fd. """

        with codecs.open(self.filename, 'r', self.output_encoding,
                         self.codec_errors) as fd:
            for line in fd:
                line = line.rstrip()
                if line.startswith('#') or not line:
                    continue
                value, key = line.split(None, 1)
                self.blacklist[key] = int(value)