def validate_server(value):
 global email_endjob, email_full, email_rss
 if ((value == '') and (email_endjob() or email_full() or email_rss())):
  return (T('Server address required'), None)
 else:
  return (None, value)

def validate_server ( value ) : global email_endjob , email_full , email_rss if ( ( value == '' ) and ( email_endjob ( ) or email_full ( ) or email_rss ( ) ) ) : return ( T ( 'Server address required' ) , None ) else : return ( None , value )
check if server non-empty .