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meet python

Install Python 3

Before you write and run Python code, you need to make sure the Python
interpreter is on your computer. In this book, you’ll start out with Release 3 of
Python, the very latest (and best) version of the language.
A release of Python might already be on your computer. Mac OS X comes
with Python 2 preinstalled, as do most versions of Linux (which can also ship
with Release 3). Windows, in contrast, doesn’t include any release of Python.
Let’s check your computer for Python 3. Open up a command-line prompt
and, if you are using Mac OS X or Linux, type:

python3 -V
Do this!
That’s an UPPERCASE
“v”, by the way.
On Windows, use this command:
c:\Python31\python.exe -V
If Python 3 is missing from
your computer, download
a copy for your favorite OS
Using the from the www.python.org
website.
UPPERCASE “v”
results in the Python
version appearing on File Edit Window Help WhichPython?
$ python3 -V
screen. Python 3.1.2
$
Without the $ python3
Python 3.1.2 (r312:79360M, Mar 24 2010, 01:33:18)
UPPERCASE “v”,
you are taken [GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more info.
into the Python >>>
interpreter. >>> quit()
$
Use the quit()
command to exit
the interpreter and
return to your OS
prompt.

When you install Python 3, you also get IDLE, Python’s simple—yet
surprisingly useful— integrated development environment. IDLE includes a
color syntax-highlighting editor, a debugger, the Python Shell, and a complete
copy of Python 3’s online documentation set.

Let’s take a quick look at IDLE.

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