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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 _populate(self, fields):
 """this runs all the fields through their iget methods to mimic them freshly coming out of the db, then resets modified :param fields: dict, the fields that were passed in """

        schema = self.schema
        for k, v in fields.items():
            fields[k] = schema.fields[k].iget(self, v)

        self.modify(fields)
        self.reset_modified()