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+// 7.3.20 SpeciesConstructor(O, defaultConstructor)
+var anObject = require('./_an-object')
+ , aFunction = require('./_a-function')
+ , SPECIES = require('./_wks')('species');
+module.exports = function(O, D){
+ var C = anObject(O).constructor, S;
+ return C === undefined || (S = anObject(C)[SPECIES]) == undefined ? D : aFunction(S);
+};
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