    # File lib/fog/openstack/requests/identity/list_users.rb, line 16
            def list_users(tenant_id = nil)
              users = self.data[:users].values

              if tenant_id
                users = users.select {
                  |user| user['tenantId'] == tenant_id
                }
              end

              Excon::Response.new(
                :body   => { 'users' => users },
                :status => 200
              )
            end