Cómo desencriptar código PHP en base64

<?php // This file is protected by copyright law and provided under license. Reverse engineering of this file is strictly prohibited.
$OOO0O0O00=__FILE__;$O00O00O00=__LINE__;$OO00O0000=2180;eval((base64_decode('JE8wMDBPME8wMD1mb3BlbigkT09PME8wTzAwLCdyYicpO3doaWxlKC0tJE8wME8wME8wMClmZ2V0cygkTzAwME8wTzAwLDEwMjQpO2ZnZXRzKCRPMDAwTzBPMDAsNDA5Nik7JE9PMDBPMDBPMD0oYmFzZTY0X2RlY29kZShzdHJ0cihmcmVhZCgkTzAwME8wTzAwLDM3MiksJ0VudGVyeW91d2toUkhZS05XT1VUQWFCYkNjRGRGZkdnSWlKakxsTW1QcFFxU3NWdlh4WnowMTIzNDU2Nzg5Ky89JywnQUJDREVGR0hJSktMTU5PUFFSU1RVVldYWVphYmNkZWZnaGlqa2xtbm9wcXJzdHV2d3h5ejAxMjM0NTY3ODkrLycpKSk7ZXZhbCgkT08wME8wME8wKTs=')));return;?>
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

$OO00O0000=2180;

$O000O0O00=fopen($__FILE__,'rb');

while(--$__LINE__)
	fgets($fopen($__FILE__,'rb'),1024);
	fgets($fopen($__FILE__,'rb'),4096);
	eval(base64_decode(strtr(fread($fopen($__FILE__,'rb'),372),'EnteryouwkhRHYKNWOUTAaBbCcDdFfGgIiJjLlMmPpQqSsVvXxZz0123456789+/=','ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'))));