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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 delete(self):
 """ Delete the instance from redis storage. """

        # Delete each field
        for field_name in self._fields:
            field = self.get_field(field_name)
            if not isinstance(field, PKField):
                # pk has no stored key
                field.delete()
        # Remove the pk from the model collection
        self.connection.srem(self.get_field('pk').collection_key, self._pk)
        # Deactivate the instance
        delattr(self, "_pk")