Deepstream python api Multiplex detection

**• Hardware Platform (Jetson / GPU):dGPU**
**• DeepStream Version:5.1**
**• JetPack Version (valid for Jetson only)**
**• TensorRT Version:7.2.3**
**• NVIDIA GPU Driver Version (valid for GPU only):11.1**
**• Issue Type( questions, new requirements, bugs):questions**

Hello, in test3, the python SDK environment, I want to apply my trained model. How should I replace it?