diff --git a/lua/dap-python.lua b/lua/dap-python.lua
index 5c4f993..4873b15 100644
--- a/lua/dap-python.lua
+++ b/lua/dap-python.lua
@@ -38,6 +38,7 @@ local function default_runner()
       end
       f:close()
     end
+    return 'unittest'
   else
     return 'unittest'
   end