id() function in python
<blockquote>
  <h3>id(object)</h3>
  
  <p>This is an integer (or long integer) which is guaranteed to be unique and constant for this object during its lifetime. </p>
</blockquote>

<p>Can you explain this output? Why does <code>j</code>'s id change?</p>

<pre><code>&gt;&gt;&gt; i=10  
&gt;&gt;&gt; id(i)  
6337824  
&gt;&gt;&gt; j=10  
&gt;&gt;&gt; id(j)  
6337824  
&gt;&gt;&gt; j=j+1  
&gt;&gt;&gt; id(j)  
6337800  
&gt;&gt;&gt; id(i)  
6337824  
</code></pre>
