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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_dynamic_versions(self):
 """ Call the `delete` method of all dynamic versions of the current field found in the inventory then clean the inventory. """

        if self.dynamic_version_of:
            raise ImplementationError(u'"_delete_dynamic_versions" can only be '
                                      u'executed on the base field')
        inventory = self._inventory
        for dynamic_part in inventory.smembers():
            name = self.get_name_for(dynamic_part)
            # create the field
            new_field = self._create_dynamic_version()
            new_field.name = name
            new_field._dynamic_part = dynamic_part  # avoid useless computation
            new_field._attach_to_model(self._model)
            new_field._attach_to_instance(self._instance)
            # and delete its content
            new_field.delete()

        inventory.delete()