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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 _validate_field_can_be_tagged_with_redactor(self, field):
 """ Validates that the field type can be annotated and that alias does not have conflicting annotations. """

        if is_alias(field.data_type):
            raise InvalidSpec(
                "Redactors can only be applied to alias definitions, not "
                "to alias references.",
                field._ast_node.lineno, field._ast_node.path)

        self._validate_object_can_be_tagged_with_redactor(field)