authenticate = (username, password, securityToken) =>
  new Promise((resolve, reject) => {
    // Authenticate using multi user mode
    org.authenticate(
      {
        username: username,
        password: password,
        securityToken: securityToken
      },
      (error, response) => {
        if (!error) {
          resolve(response)
        } else {
          reject(error)
        }
      }
    )
  })
Authenticate to login a user in the org
@param {string} username - e.g. john@example.com
@param {string} password
@param {string} securityToken - Your user's security token.
                           This can be reset in the org if needed.