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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 input_streams(self):
 """Return a list of DataStream objects for all singular input streams. This function only returns individual streams, not the streams that would be selected from a selector like 'all outputs' for example. Returns: list(DataStream):
 A list of all of the individual DataStreams that are inputs of the node. Input selectors that select multiple streams are not included """


        streams = []

        for walker, _trigger in self.inputs:
            if walker.selector is None or not walker.selector.singular:
                continue

            streams.append(walker.selector.as_stream())

        return streams