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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th23</font></span>: <a NAME="T23"><span class="comment"><font color="firebrick">:: ZFMODEL2:23</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">M</font> being   non  <a href="xboole_0.html#V1" title="XBOOLE_0:attr.1">empty</a>   <a href="hidden.html#M2" title="HIDDEN:mode.2">set</a>  holds   <a href="partfun1.html#K6" title="PARTFUN1:func.6">id</a> <font color="Olive" title="b1">M</font> <a href="zfmodel1.html#R1" title="ZFMODEL1:pred.1">is_definable_in</a> <font color="Olive" title="b1">M</font></div></div>
