code: public final ListTenantsPagedResponse listTenants(String parent) {
      ListTenantsRequest request = ListTenantsRequest.newBuilder().setParent(parent).build();
      return listTenants(request);
    }
docs: Lists all tenants associated with the project.
  
  <p>Sample code:
  
  <pre><code>
  try (TenantServiceClient tenantServiceClient = TenantServiceClient.create()) {
  ProjectName parent = ProjectName.of("[PROJECT]");
  for (Tenant element : tenantServiceClient.listTenants(parent.toString()).iterateAll()) {
  // doThingsWith(element);
  }
  }
  </code></pre>
  
  @param parent Required.
  <p>Resource name of the project under which the tenant is created.
  <p>The format is "projects/{project_id}", for example, "projects/api-test-project".
  @throws com.google.api.gax.rpc.ApiException if the remote call fails