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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 iterstruct(self):
 """Yield data structures built from the JSON header specifications in a table"""

        from rowgenerators.rowpipe.json import add_to_struct

        json_headers = self.json_headers

        for row in islice(self, 1, None): # islice skips header
            d = {}
            for pos, jh in json_headers:
                add_to_struct(d, jh, row[pos])
            yield d