How to debug on macOS

On Ubuntu, I can run “gdb --args python my_script.py” and set breakpoints in C++ ops. And then it works well.
On macOS, I have built a debug version on macOS successful
ly.
export DEBUG=1
MACOSX_DEPLOYMENT_TARGET=10.9 CC=clang CXX=clang++ python setup.py install
But, I don’t know how to set bps in cpp codes. Anyone can help me?
Thanks.