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copied!<p>The quick answer:</p> <pre><code>f=open('filename') lines=f.readlines() print lines[25] print lines[29] </code></pre> <p>or:</p> <pre><code>lines=[25, 29] i=0 f=open('filename') for line in f: if i in lines: print i i+=1 </code></pre> <p>There is a more elegant solution for extracting many lines: <a href="http://docs.python.org/library/linecache.html" rel="noreferrer">linecache</a> (courtesy of <a href="https://stackoverflow.com/questions/620367/python-how-to-jump-to-a-particular-line-in-a-huge-text-file">"python: how to jump to a particular line in a huge text file?"</a>, a previous stackoverflow.com question).</p> <p>Quoting the python documentation linked above:</p> <pre><code>>>> import linecache >>> linecache.getline('/etc/passwd', 4) 'sys:x:3:3:sys:/dev:/bin/sh\n' </code></pre> <p>Change the <code>4</code> to your desired line number, and you're on. Note that 4 would bring the fifth line as the count is zero-based.</p> <p>If the file might be very large, and cause problems when read into memory, it might be a good idea to take <a href="https://stackoverflow.com/questions/2081836/reading-specific-lines-only-python/2081880#2081880">@Alok's advice and use enumerate()</a>.</p> <p><strong>To Conclude:</strong></p> <ul> <li>Use <code>fileobject.readlines()</code> or <code>for line in fileobject</code> as a quick solution for small files. </li> <li>Use <code>linecache</code> for a more elegant solution, which will be quite fast for reading many files, possible repeatedly.</li> <li>Take <a href="https://stackoverflow.com/questions/2081836/reading-specific-lines-only-python/2081880#2081880">@Alok's advice and use <code>enumerate()</code></a> for files which could be very large, and won't fit into memory. Note that using this method might slow because the file is read sequentially.</li> </ul>

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