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#### Section/Content To Improve
https://github.com/axios/axios/blob/master/CHANGELOG.md

#### Suggested Improvement
Please add 0.21.1 to the Changelog.

#### Relevant File(s)
https://github.com/axios/axios/blob/master/CHANGELOG.md
dist/axios.js
* @returns {Object} New object resulting from merging config2 to config1
	 */
	module.exports = function mergeConfig(config1, config2) {
	  
	  config2 = config2 || {};
	  var config = {};
	
	  var valueFromConfig2Keys = ['url', 'method', 'data'];
	  var mergeDeepPropertiesKeys = ['headers', 'auth', 'proxy', 'params'];
	  var defaultToConfig2Keys = [
	    'baseURL', 'transformRequest', 'transformResponse', 'paramsSerializer',
	    'timeout', 'timeoutMessage', 'withCredentials', 'adapter', 'responseType', 'xsrfCookieName',
	    'xsrfHeaderName', 'onUploadProgress', 'onDownloadProgress', 'decompress',
	    'maxContentLength', 'maxBodyLength', 'maxRedirects', 'transport', 'httpAgent',
	    'httpsAgent', 'cancelToken', 'socketPath', 'responseEncoding'
	  ];
	  var directMergeKeys = ['validateStatus'];
	
	  function getMergedValue(target, source) {
	    if (utils.isPlainObject(target) && utils.isPlainObject(source)) {
	      return utils.merge(target, source);
	    } else if (utils.isPlainObject(source)) {
	      return utils.merge({}, source);
	    } else if (utils.isArray(source)) {
	      return source.slice();
	    }
	    return source;
	  }
	
	  function mergeDeepProperties(prop) {