def get_user_by_username(name)
      resp = request('getUserByUsername', username: name)['user']
      resp['user_id'].nil? ? nil : User.new(self, resp)
    end
def get_user_by_username(name)
      resp = request('getUserByUsername', username: name)['user']
      resp['user_id'].nil? ? nil : User.new(self, resp)
    end
Find user by username