old_contents: var _ = require('lodash');
  
  /**
   * Create base instance for SMS
   * @param {Object} [_config]
   * @constructor
   */
  function BaseSms(_config) {
    this._config = {};
  
    _.forOwn(_config, function (value, key) {
      this.set(key, value);
    }.bind(this));
  }
  
  /**
   * Get configuration value
   * @param {String} [path]
   * @returns {*}
   */
  BaseSms.prototype.get = function (path) {
    return typeof path === 'undefined' ? this._config : _.get(this._config, path);
  };
  
  /**
   * Set configuration value
   * @param {String} path
   * @param {*} value
   * @returns {BaseSms}
   */
  BaseSms.prototype.set = function (path, value) {
    _.set(this._config, path, value);
    return this;
  };
  
  /**
   * Get provider for sending notifications
   * @returns {*}
   */
  BaseSms.prototype.getProvider = function () {
    return this._provider;
  };
  
  /**
   * Set new provider to this pusher
   * @param {*} provider
   * @returns {BaseSms}
   */
  BaseSms.prototype.setProvider = function (provider) {
    this._provider = provider;
    return this;
  };
  
  BaseSms.prototype.send = _;
  
  module.exports = BaseSms;
  
new_contents: import _ from 'lodash';
  
  export default class BaseSms {
    constructor(_config) {
      this._config = {};
      this._provider = {};
  
      _.assign(this._config, _config);
    }
  
    /**
     * Get configuration value
     * @param {String} [path]
     * @returns {*}
     */
    get(path) {
      return typeof path === 'undefined' ? this._config : _.get(this._config, path);
    }
  
    /**
     * Set configuration value
     * @param {String} path
     * @param {*} value
     * @returns {BaseSms}
     */
    set(path, value) {
      _.set(this._config, path, value);
      return this;
    }
  
    /**
     * Get provider for sending notifications
     * @returns {*}
     */
    getProvider() {
      return this._provider;
    }
  
    /**
     * Set new provider to this pusher
     * @param {*} provider
     * @returns {BaseSms}
     */
    setProvider(provider) {
      this._provider = provider;
      return this;
    }
  }
  
subject: Rewrite BaseSms with ES6