def is_field_error(errors):
 if isinstance(errors, (list, tuple)):
  for e in errors:
   if isinstance(e, string_types):
    return True
 return False

def is_field_error ( errors ) : if isinstance ( errors , ( list , tuple ) ) : for e in errors : if isinstance ( e , string_types ) : return True return False
check if wtforms field has error without checking its children .