code: function SendmailTransport(options) {
      options = options || {};
  
      // use a reference to spawn for mocking purposes
      this._spawn = spawn;
  
      this.options = options;
  
      this.name = 'Sendmail';
      this.version = packageData.version;
  
      this.path = 'sendmail';
      this.args = false;
  
      if (typeof options === 'string') {
          this.path = options;
      } else if (typeof options === 'object') {
          if (options.path) {
              this.path = options.path;
          }
          if (Array.isArray(options.args)) {
              this.args = options.args;
          }
      }
  }
docs: <p>Generates a Transport object for Amazon Sendmail with aws-sdk</p>
  
  <p>Possible options can be the following:</p>
  
  <ul>
  <li><b>accessKeyId</b> - AWS access key (optional)</li>
  <li><b>secretAccessKey</b> - AWS secret (optional)</li>
  <li><b>region</b> - optional region (defaults to <code>'us-east-1'</code>)
  </ul>
  
  @constructor
  @param {Object} optional config parameter for the AWS Sendmail service