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define(['./_Symbol'], function(Symbol) {
  /** Used as a safe reference for `undefined` in pre-ES5 environments. */  var undefined;
  /** Used to convert symbols to primitives and strings. */  var symbolProto = Symbol ? Symbol.prototype : undefined,      symbolValueOf = symbolProto ? symbolProto.valueOf : undefined;
  /**   * Creates a clone of the `symbol` object.   *   * @private   * @param {Object} symbol The symbol object to clone.   * @returns {Object} Returns the cloned symbol object.   */  function cloneSymbol(symbol) {    return symbolValueOf ? Object(symbolValueOf.call(symbol)) : {};  }
  return cloneSymbol;});