42 lines
1.5 KiB
Python
Executable File
42 lines
1.5 KiB
Python
Executable File
from __future__ import annotations
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from typing import TYPE_CHECKING
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from typing import Any
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from typing import NoReturn
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from narwhals._interchange.dataframe import map_interchange_dtype_to_narwhals_dtype
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if TYPE_CHECKING:
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from narwhals.typing import DTypes
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class InterchangeSeries:
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def __init__(self, df: Any, dtypes: DTypes) -> None:
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self._native_series = df
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self._dtypes = dtypes
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def __narwhals_series__(self) -> Any:
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return self
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def __native_namespace__(self) -> NoReturn:
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msg = (
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"Cannot access native namespace for metadata-only series with unknown backend. "
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"If you would like to see this kind of object supported in Narwhals, please "
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"open a feature request at https://github.com/narwhals-dev/narwhals/issues."
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)
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raise NotImplementedError(msg)
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def __getattr__(self, attr: str) -> Any:
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if attr == "dtype":
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return map_interchange_dtype_to_narwhals_dtype(
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self._native_series.dtype, dtypes=self._dtypes
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)
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msg = ( # pragma: no cover
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f"Attribute {attr} is not supported for metadata-only dataframes.\n\n"
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"Hint: you probably called `nw.from_native` on an object which isn't fully "
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"supported by Narwhals, yet implements `__dataframe__`. If you would like to "
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"see this kind of object supported in Narwhals, please open a feature request "
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"at https://github.com/narwhals-dev/narwhals/issues."
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)
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raise NotImplementedError(msg)
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