24 lines
778 B
Python
24 lines
778 B
Python
# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import typing as ty
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# Workaround Python's lack of an undefined sentinel
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# https://python-patterns.guide/python/sentinel-object/
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class Unset:
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def __bool__(self) -> ty.Literal[False]:
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return False
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UNSET: Unset = Unset()
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