\item[__slots__]{A declaration inside a \emph{new-style class} that saves

\item[byte code]{The internal representation of a Python program in the

{}\code{int(3.15)} coerces the floating point number to the integer, \code{3}.

Most mathematical operations have rules for coercing their arguments to a common

type. For instance, adding \code{3 + 4.5}, causes the integer \code{3} to be

coerced to be a float \code{3.0} before adding to \code{4.5} resulting in the

float \code{7.5}.}

\item[descriptor]{Any object that defines the methods \method{__get__()},

\method{__set__()}, or \method{__delete__()}. When a class attribute is a

descriptor, its special binding behavior is triggered upon attribute lookup.

Normally, writing {}\var{a.b} looks up the object \var{b} in the class

dictionary for \var{a}, but if \var{b} is a descriptor, the defined method

gets called. Understanding descriptors is a key to a deep understanding of

Python because they are the basis for many features including functions,

methods, properties, class methods, static methods, and reference to super

values. The use of \class{dict} much resembles that for \class{list}, but

the keys can be any object with a \function{__hash__} function, not just

integers starting from zero. Called a hash in Perl.}

Python coding style assumes the existence of valid keys or attributes and

style is characterized by the presence of many \keyword{try} and

{}\keyword{except} statements. The technique contrasts with the \emph{LBYL}

style that is common in many other languages such as C.}

If the module in which it is executed had enabled emph{true division} by

executing:}

importing the \module{__future__} module and evaluating its variables, you

can see when a new feature was first added to the language and when it will

become the default:

\item[GIL]{See \emph{global interpreter lock}.}

basic editor and interpreter environment that ships with the standard

distribution of Python. Good for beginners, it also serves as clear

example code for those wanting to implement a moderately

example, the expression \code{11 / 4} currently evaluates to \code{2} in

contrast to the \code{2.75} returned by float division. Also called

\emph{floor division}. When dividing two integers the outcome will always be

another integer (having the floor function applied to it). However, if one

of the operands is another numeric type (such as a \class{float}), the result

will be coerced (see \emph{coercion}) to a common type. For example, a integer

divided by a float will result in a float value, possibly with a decimal

fraction. Integer division can be forced by using the \code{//} operator

instead of the \code{/} operator.

See also, \emph{__future__}.}

making an executable which is then run. Interpreted languages typically have

{}\emph{interactive}.}

time. Examples of iterables include all sequence types (such as\class{list},

{}\class{str}, and \class{tuple}) and some non-sequence types like

an \method{__iter__} or \function{__getitem__} method. Iterables can be

\emph{iterator}, \emph{sequence} and \emph{generator}.}

exception is raised instead. At this point, the iterator object is exhausted

multiple iteration passes. A container object (such as a \class{list})

produces a fresh new iterator each time you pass it to the \function{iter()}

function or use it in a \function{for} loop. Attempting this with an iterator

will just return the same exhausted iterator object from the second iteration

pass, making it appear like an empty container.}

the \emph{EAFP} approach and is characterized the presence of many

{}\keyword{if} statements.}

maintainability by making it clear which modules implement a function. For

includes all built-in types like \class{list} and \class{dict}. Only

new-style classes can use Python's newer, versatile features like

\item[sequence]{An \emph{iterable} which supports efficient element access using

rather than a sequence because the lookups use arbitrary \emph{immutable} keys

be found by typing \code{import this} at the interactive prompt.}