nd pivot Key
 There is no needs of wrapping in transaction, when using dirty_next
 Returns RetKey, or '$end_of_table' or  throws Error</p>

<h3 class="function"><a name="dirty_prev-2">dirty_prev/2</a></h3>
<div class="spec">
<p><tt>dirty_prev(Storage::atom(), Key::any()) -&gt; RetKey::any() | '$end_of_table' | no_return()</tt><br></p>
</div><p>Dirty Previous.
 Function gets the previous key of the Storage, from given Key
 As input function gets Name of storage as atom and pivot Key
 There is no needs of wra