code: @Override
      public GetAdminAccountResult getAdminAccount(GetAdminAccountRequest request) {
          request = beforeClientExecution(request);
          return executeGetAdminAccount(request);
      }
docs: <p>
  Returns the AWS Organizations master account that is associated with AWS Firewall Manager as the AWS Firewall
  Manager administrator.
  </p>
  
  @param getAdminAccountRequest
  @return Result of the GetAdminAccount operation returned by the service.
  @throws InvalidOperationException
  The operation failed because there was nothing to do. For example, you might have submitted an
  <code>AssociateAdminAccount</code> request, but the account ID that you submitted was already set as the
  AWS Firewall Manager administrator.
  @throws ResourceNotFoundException
  The specified resource was not found.
  @throws InternalErrorException
  The operation failed because of a system problem, even though the request was valid. Retry your request.
  @sample AWSFMS.GetAdminAccount
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/fms-2018-01-01/GetAdminAccount" target="_top">AWS API
  Documentation</a>