1 | \chapter{Introduction}
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2 | \label{intro}
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3 |
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4 | The ``Python library'' contains several different kinds of components.
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5 |
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6 | It contains data types that would normally be considered part of the
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7 | ``core'' of a language, such as numbers and lists. For these types,
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8 | the Python language core defines the form of literals and places some
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9 | constraints on their semantics, but does not fully define the
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10 | semantics. (On the other hand, the language core does define
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11 | syntactic properties like the spelling and priorities of operators.)
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12 |
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13 | The library also contains built-in functions and exceptions ---
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14 | objects that can be used by all Python code without the need of an
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15 | \keyword{import} statement. Some of these are defined by the core
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16 | language, but many are not essential for the core semantics and are
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17 | only described here.
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18 |
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19 | The bulk of the library, however, consists of a collection of modules.
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20 | There are many ways to dissect this collection. Some modules are
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21 | written in C and built in to the Python interpreter; others are
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22 | written in Python and imported in source form. Some modules provide
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23 | interfaces that are highly specific to Python, like printing a stack
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24 | trace; some provide interfaces that are specific to particular
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25 | operating systems, such as access to specific hardware; others provide
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26 | interfaces that are
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27 | specific to a particular application domain, like the World Wide Web.
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28 | Some modules are available in all versions and ports of Python; others
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29 | are only available when the underlying system supports or requires
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30 | them; yet others are available only when a particular configuration
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31 | option was chosen at the time when Python was compiled and installed.
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32 |
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33 | This manual is organized ``from the inside out:'' it first describes
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34 | the built-in data types, then the built-in functions and exceptions,
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35 | and finally the modules, grouped in chapters of related modules. The
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36 | ordering of the chapters as well as the ordering of the modules within
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37 | each chapter is roughly from most relevant to least important.
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38 |
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39 | This means that if you start reading this manual from the start, and
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40 | skip to the next chapter when you get bored, you will get a reasonable
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41 | overview of the available modules and application areas that are
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42 | supported by the Python library. Of course, you don't \emph{have} to
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43 | read it like a novel --- you can also browse the table of contents (in
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44 | front of the manual), or look for a specific function, module or term
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45 | in the index (in the back). And finally, if you enjoy learning about
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46 | random subjects, you choose a random page number (see module
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47 | \refmodule{random}) and read a section or two. Regardless of the
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48 | order in which you read the sections of this manual, it helps to start
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49 | with chapter \ref{builtin}, ``Built-in Types, Exceptions and
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50 | Functions,'' as the remainder of the manual assumes familiarity with
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51 | this material.
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52 |
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53 | Let the show begin!
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