部分範囲から

extension PartialRangeFrom: TensorRangeExpression where Bound == Int
extension PartialRangeFrom where Bound == Int
extension PartialRangeFrom : PythonConvertible where Bound : PythonConvertible
extension PartialRangeFrom : ConvertibleFromPython
where Bound : ConvertibleFromPython
`Bound` == `Int` の場合に利用可能
`Bound` : `PythonConvertible` で利用可能
`Bound` : `ConvertibleFromPython` で利用可能