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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 pipe_createrss(context=None, _INPUT=None, conf=None, **kwargs):
 """An operator that converts a source into an RSS stream. Not loopable. """

    conf = DotDict(conf)

    for item in _INPUT:
        item = DotDict(item)

        yield {
            value: item.get(conf.get(key, **kwargs))
            for key, value in RSS_FIELDS.items()}