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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(self, data=''):
        '''
        Optionally add pending data, switch into streaming mode, and yield
        result chunks.

        :yields: result chunks
        :ytype: str
        '''
        self.streaming = True
        self.pending += data
        for i in self:
            yield i