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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
* @param {string} url The base of the url (e.g., http://www.google.com)
	 * @param {object} [params] The params to be appended
	 * @returns {string} The formatted url
	 */
	module.exports = function buildURL(url, params, paramsSerializer) {
	  
	  if (!params) {
	    return url;
	  }
	
	  var serializedParams;
	  if (paramsSerializer) {
	    serializedParams = paramsSerializer(params);
	  } else if (utils.isURLSearchParams(params)) {
	    serializedParams = params.toString();
	  } else {
	    var parts = [];
	
	    utils.forEach(params, function serialize(val, key) {
	      if (val === null || typeof val === 'undefined') {
	        return;
	      }
	
	      if (utils.isArray(val)) {
	        key = key + '[]';
	      } else {
	        val = [val];
	      }
	
	      utils.forEach(val, function parseValue(v) {