diff --git a/src/connector/python/taos/cinterface.py b/src/connector/python/taos/cinterface.py
index 1223b4544899dd83d3f1ea1a519def035de8ebcf..6182d7fa7bb8c551dfc1b5afdc7e112173dd1692 100644
--- a/src/connector/python/taos/cinterface.py
+++ b/src/connector/python/taos/cinterface.py
@@ -64,6 +64,8 @@ _libtaos.taos_consume.restype = ctypes.c_void_p
 _libtaos.taos_fetch_lengths.restype = ctypes.POINTER(ctypes.c_int)
 _libtaos.taos_free_result.restype = None
 _libtaos.taos_query.restype = ctypes.POINTER(ctypes.c_void_p)
+_libtaos.taos_schemaless_insert.restype = ctypes.c_void_p
+
 try:
     _libtaos.taos_stmt_errstr.restype = c_char_p
 except AttributeError: