\setindexsubitem{(built-in exception base class)}

The following exceptions are only used as base classes for other

\begin{excdesc}{Exception}

The root class for exceptions. All built-in exceptions are derived

still be rescued (by deleting some objects). The associated value is

a string indicating what kind of (internal) operation ran out of memory.

Note that because of the underlying memory management architecture

always be able to completely recover from this situation; it

nevertheless raises an exception so that a stack traceback can be

printed, in case a run-away program was the cause.

Raised when the result of an arithmetic operation is too large to be

represented. This cannot occur for long integers (which would rather

raise \exception{MemoryError} than give up). Because of the lack of

floating point operations also aren't checked. For plain integers,

all operations that can overflow are checked except left shift, where

typical applications prefer to drop bits than raise an exception.

This exception is raised by the \function{sys.exit()} function. When it

is not handled, the Python interpreter exits; no stack traceback is

printed. If the associated value is a plain integer, it specifies the

\code{None}, the exit status is zero; if it has another type (such as

a string), the object's value is printed and the exit status is one.

A call to \function{sys.exit()} is translated into an exception so that

clean-up handlers (\keyword{finally} clauses of \keyword{try} statements)

can be executed, and so that a debugger can execute a script without

details about the type mismatch.

\end{excdesc}

\begin{excdesc}{UnicodeError}

Raised when a Unicode-related encoding or decoding error occurs. It

is a subclass of \exception{ValueError}.

\end{excdesc}

\begin{excdesc}{ValueError}