Trying to understand Python loop using underscore and input
<p>One more tip - if anyone is learning Python on HackerRank, knowing this is critical for starting out.</p>

<p>I'm trying to understand this code:</p>

<pre><code>    stamps = set()
    for _ in range(int(raw_input())):
        print 'underscore is', _
        stamps.add(raw_input().strip())
        print stamps
</code></pre>

<p>Output:</p>

<pre><code>    &gt;&gt;&gt;2 
    underscore is 0
    &gt;&gt;&gt;first
    set(['first'])
    underscore is 1
    &gt;&gt;&gt;second
    set(['second', 'first'])
</code></pre>

<ol>
<li><p>I put 2 as the first raw input. How does the function know that I'm only looping twice? This is throwing me off because it isn't the typical...for i in xrange(0,2) structure. </p></li>
<li><p>At first my thinking was the underscore repeats the last command in shell. So I added print statements in the code to see the value of underscore...but the values just show the 0 and 1, like the typical loop structure.</p></li>
</ol>

<p>I read through this post already and I still can't understand which of those 3 usages of underscore is being used. </p>

<p><a href="http://stackoverflow.com/questions/5893163/what-is-the-purpose-of-the-single-underscore-variable-in-python">What is the purpose of the single underscore &quot;_&quot; variable in Python?</a></p>

<p>I'm just starting to learn Python so easy explanations would be much appreciated!</p>

<p>The underscore is like a normal variable in your program.</p>

python loops input