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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 items(self):
 """ Schema or a list of schemas describing particular elements of the object. A single schema applies to all the elements. Each element of the object must match that schema. A list of schemas describes particular elements of the object. """

        value = self._schema.get("items", {})
        if not isinstance(value, (list, dict)):
            raise SchemaError(
                "items value {0!r} is neither a list nor an object".
                format(value))
        return value