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id="launch-shell">\n                <li>\n                    <a class="button prompt" id="start-shell" data-shell-container="#dive-into-python" href="/shell/">&gt;_\n                        <span class="message">Launch Interactive Shell</span>\n                    </a>\n                </li>\n            </ul>\n\n            <ul class="slides menu">\n                \n                <li>\n                    <div class="slide-code"><pre><code><span class="comment"># Python 3: Fibonacci series up to n</span>\r\n>>> def fib(n):\r\n>>>     a, b = 0, 1\r\n>>>     while a &lt; n:\r\n>>>         print(a, end=\' \')\r\n>>>         a, b = b, a+b\r\n>>>     print()\r\n>>> fib(1000)\r\n<span class="output">0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987</span></code></pre></div>\n                    <div class="slide-copy"><h1>Functions Defined</h1>\r\n<p>The core of extensible programming is defining functions. Python allows mandatory and optional arguments, keyword arguments, and even arbitrary argument lists. <a href="//docs.python.org/3/tutorial/controlflow.html#defining-functions">More about defining functions in Python&nbsp;3</a></p></div>\n                </li>\n                \n                <li>\n                    <div class="slide-code"><pre><code><span class="comment"># Python 3: List comprehensions</span>\r\n>>> fruits = [\'Banana\', \'Apple\', \'Lime\']\r\n>>> loud_fruits = [fruit.upper() for fruit in fruits]\r\n>>> print(loud_fruits)\r\n<span class="output">[\'BANANA\', \'APPLE\', \'LIME\']</span>\r\n\r\n<span class="comment"># List and the enumerate function</span>\r\n>>> list(enumerate(fruits))\r\n<span class="output">[(0, \'Banana\'), (1, \'Apple\'), (2, \'Lime\')]</span></code></pre></div>\n                    <div class="slide-copy"><h1>Compound Data Types</h1>\r\n<p>Lists (known as arrays in other languages) are one of the compound data types that Python understands. Lists can be indexed, sliced and manipulated with other built-in functions. <a href="//docs.python.org/3/tutorial/introduction.html#lists">More about lists in Python&nbsp;3</a></p></div>\n                </li>\n                \n                <li>\n                    <div class="slide-code"><pre><code><span class="comment"># Python 3: Simple arithmetic</span>\r\n>>> 1 / 2\r\n<span class="output">0.5</span>\r\n>>> 2 ** 3\r\n<span class="output">8</span>\r\n>>> 17 / 3  <span class="comment"># classic division returns a float</span>\r\n<span class="output">5.666666666666667</span>\r\n>>> 17 // 3  <span class="comment"># floor division</span>\r\n<span class="output">5</span></code></pre></div>\n                    <div class="slide-copy"><h1>Intuitive Interpretation</h1>\r\n<p>Calculations are simple with Python, and expression syntax is straightforward: the operators <code>+</code>, <code>-</code>, <code>*</code> and <code>/</code> work as expected; parentheses <code>()</code> can be used for grouping. <a href="http://docs.python.org/3/tutorial/introduction.html#using-python-as-a-calculator">More about simple math functions in Python&nbsp;3</a>.</p></div>\n                </li>\n                \n                <li>\n                    <div class="slide-code"><pre><code><span class="comment"># Python 3: Simple output (with Unicode)</span>\r\n>>> print("Hello, I\'m Python!")\r\n<span class="output">Hello, I\'m Python!</span>\r\n\r\n<span class="comment"># Input, assignment</span>\r\n>>> name = input(\'What is your name?\\n\')\r\n>>> print(\'Hi, %s.\' % name)\r\n<span class="output">What is your name?\r\nPython\r\nHi, Python.</span></code></pre></div>\n                    <div class="slide-copy"><h1>Quick &amp; Easy to Learn</h1>\r\n<p>Experienced programmers in any other language can pick up Python very quickly, and beginners find the clean syntax and indentation structure easy to learn. <a href="//docs.python.org/3/tutorial/">Whet your appetite</a> with our Python&nbsp;3 overview.</p>\r\n                   </div>\n                </li>\n                \n                <li>\n                    <div class="slide-code"><pre><code><span class="comment"># For loop on a list</span>\r\n>>> numbers = [2, 4, 6, 8]\r\n>>> product = 1\r\n>>> for number in numbers:\r\n...    product = product * number\r\n... \r\n>>> print(\'The product is:\', product)\r\n<span class="output">The product is: 384</span></code></pre></div>\n                    <div class="slide-copy"><h1>All the Flow You&rsquo;d Expect</h1>\r\n<p>Python knows the usual control flow statements that other languages speak &mdash; <code>if</code>, <code>for</code>, <code>while</code> and <code>range</code> &mdash; with some of its own twists, of course. <a href="//docs.python.org/3/tutorial/controlflow.html">More control flow tools in Python&nbsp;3</a></p></div>\n                </li>\n                \n            </ul>\n        </div>\n\n\n                </div>\n\n                \n        <div class="introduction">\n            <p>Python is a programming language that lets you work quickly <span class="breaker"></span>and integrate systems more effectively. <a class="readmore" href="/doc/">Learn More</a></p>\n        </div>\n\n\n             </div><!-- end .container -->\n        </header>\n\n        <div id="content" class="content-wrapper">\n            <!-- Main Content Column -->\n            <div class="container">\n\n                <section class="main-content " role="main">\n\n                    \n                    \n\n                    \n\n                    \n\n                \n\n                <div class="row">\n\n                    <div class="small-widget get-started-widget">\n                        <h2 class="widget-title"><span aria-hidden="true" class="icon-get-started"></span>Get Started</h2>\r\n<p>Whether you\'re new to programming or an experienced developer, it\'s easy to learn and use Python.</p>\r\n<p><a href="/about/gettingstarted/">Start with our Beginner&rsquo;s Guide</a></p>\n                    </div>\n\n                    <div class="small-widget download-widget">\n                        <h2 class="widget-title"><span aria-hidden="true" class="icon-download"></span>Download</h2>\n<p>Python source code and installers are available for download for all versions!</p>\n<p>Latest: <a href="/downloads/release/python-374/">Python 3.7.4</a></p>\n                    </div>\n\n                    <div class="small-widget documentation-widget">\n                        <h2 class="widget-title"><span aria-hidden="true" class="icon-documentation"></span>Docs</h2>\r\n<p>Documentation for Python\'s standard library, along with tutorials and guides, are available online.</p>\r\n<p><a href="https://docs.python.org">docs.python.org</a></p>\n                    </div>\n\n                    <div class="small-widget jobs-widget last">\n                        <h2 class="widget-title"><span aria-hidden="true" class="icon-jobs"></span>Jobs</h2>\r\n<p>Looking for work or have a Python related position that you\'re trying to hire for? 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Source code of the solution(s):