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