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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 feed_data(self, data):
 """Feed new data into the MultiPart parser or the data stream"""

        if data:
            self._bytes.append(data)
            if self.parser.stream:
                self.parser.stream(self)
            else:
                self.parser.buffer.extend(data)