Copy value of list not reference : <p>I have a list that i want to compare to after it gets modified. The previous_list = current_list followed by a modification to the current_list. But the issue i have is anytime the current_list is updated, the previous_list is also updated because everything in python is a reference. Ive tried, </p>

<pre><code>previous_list = current_list[:]
previous_list = current_list.copy()
previous_list = list(current_list)
</code></pre>

<p>but none of these work, every time current_list is updated the previous list is updated immediately without reading this line,</p>

<pre><code>previous_list = current_list[:] 
</code></pre>

<p>again. </p>

<p>My goal is to have a while loop the runs until the list are equal. Each loop the current_list is modified after the previous_list is updated with the current_value. I thought the solution was using one of the copy methods above to create a copy of the list and assign but maybe that is a reference too then.</p>
