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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 iterjson(self, *args, **kwargs):
 """Yields the data structures from iterstruct as JSON strings"""

        from rowgenerators.rowpipe.json import VTEncoder
        import json

        if 'cls' not in kwargs:
            kwargs['cls'] = VTEncoder

        for s in self.iterstruct:
            yield (json.dumps(s, *args, **kwargs))