Python: how can I get rid of the second element of each sublist?
<p>I have a list of sublists, such as:</p>

<p>[[501, 4], [501, 4], [501, 4], [501, 4]]</p>

<p>How can I get rid of the second element for each sublist ? (i.e. 4)</p>

<p>[501, 501, 501, 501]</p>

<p>Should I iterate the list or is there a faster way ?
thanks</p>
