mirror of https://github.com/python/cpython
34 lines
1.0 KiB
TeX
34 lines
1.0 KiB
TeX
\section{Built-in Constants}
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A small number of constants live in the built-in namespace. They are:
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\begin{datadesc}{False}
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The false value of the \class{bool} type.
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\versionadded{2.3}
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\end{datadesc}
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\begin{datadesc}{True}
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The true value of the \class{bool} type.
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\versionadded{2.3}
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\end{datadesc}
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\begin{datadesc}{None}
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The sole value of \code{\refmodule{types}.NoneType}. \code{None} is
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frequently used to represent the absence of a value, as when default
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arguments are not passed to a function.
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\end{datadesc}
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\begin{datadesc}{NotImplemented}
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Special value which can be returned by the ``rich comparison''
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special methods (\method{__eq__()}, \method{__lt__()}, and friends),
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to indicate that the comparison is not implemented with respect to
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the other type.
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\end{datadesc}
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\begin{datadesc}{Ellipsis}
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The same as \code{...}.
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Special value used mostly in conjunction with extended slicing syntax
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for user-defined container data types.
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% XXX Someone who understands extended slicing should fill in here.
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\end{datadesc}
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