| 1234567891011121314151617181920212223242526272829303132333435 | 'use strict';var toStr = Object.prototype.toString;var hasSymbols = require('has-symbols')();if (hasSymbols) {	var symToStr = Symbol.prototype.toString;	var symStringRegex = /^Symbol\(.*\)$/;	var isSymbolObject = function isRealSymbolObject(value) {		if (typeof value.valueOf() !== 'symbol') {			return false;		}		return symStringRegex.test(symToStr.call(value));	};	module.exports = function isSymbol(value) {		if (typeof value === 'symbol') {			return true;		}		if (toStr.call(value) !== '[object Symbol]') {			return false;		}		try {			return isSymbolObject(value);		} catch (e) {			return false;		}	};} else {	module.exports = function isSymbol(value) {		// this environment does not support Symbols.		return false && value;	};}
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