| 1234567891011121314151617 | 'use strict';var validTypes = { object: true, symbol: true };module.exports = function () {	var symbol;	if (typeof Symbol !== 'function') return false;	symbol = Symbol('test symbol');	try { String(symbol); } catch (e) { return false; }	// Return 'true' also for polyfills	if (!validTypes[typeof Symbol.iterator]) return false;	if (!validTypes[typeof Symbol.toPrimitive]) return false;	if (!validTypes[typeof Symbol.toStringTag]) return false;	return true;};
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