# Expanding Python with C++ modules
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## Top

Questions to [David Rotermund](mailto:davrot@uni-bremen.de)


### .env file

**Change the directories and parameters according you system.**

```Makefile
PYBIN=~/P3.11/bin/
CC=/usr/lib64/ccache/clang++
NVCC=/usr/local/cuda-12/bin/nvcc -allow-unsupported-compiler 

PARAMETERS_O_CPU = -O3 -std=c++14 -fPIC -Wall -fopenmp=libomp
PARAMETERS_Linker_CPU = -shared -lm -lomp -lstdc++ -Wall

PARAMETERS_O_GPU= -O3 -std=c++14 -ccbin=$(CC) \
    -Xcompiler "-fPIC -Wall -fopenmp=libomp"   
PARAMETERS_Linker_GPU=-Xcompiler "-shared -lm -lomp -lstdc++ -Wall"

O_DIRS = o/
```

### Makefile
```Makefile
include .env
export

name = MyModule
type = CPU

PYPOSTFIX := $(shell $(PYBIN)python3-config --extension-suffix)
PYBIND11INCLUDE := $(shell $(PYBIN)python3 -m pybind11 --includes)
PARAMETERS_O = $(PARAMETERS_O_CPU) $(PYBIND11INCLUDE) 
PARAMETERS_Linker = $(PARAMETERS_Linker_CPU)

so_file = Py$(name)$(type)$(PYPOSTFIX)
pyi_file = Py$(name)$(type).pyi
all: ../$(so_file)

$(O_DIRS)$(name)$(type).o: $(name)$(type).h $(name)$(type).cpp
	mkdir -p $(O_DIRS) 
	$(CC) $(PARAMETERS_O) -c $(name)$(type).cpp -o $(O_DIRS)$(name)$(type).o

$(O_DIRS)Py$(name)$(type).o: $(name)$(type).h Py$(name)$(type).cpp 
	mkdir -p $(O_DIRS)
	$(CC) $(PARAMETERS_O) -c Py$(name)$(type).cpp -o $(O_DIRS)Py$(name)$(type).o

../$(so_file): $(O_DIRS)$(name)$(type).o $(O_DIRS)Py$(name)$(type).o
	$(CC) $(PARAMETERS_Linker) -o ../$(so_file) $(O_DIRS)$(name)$(type).o $(O_DIRS)Py$(name)$(type).o


#######################
clean:
	rm -rf $(O_DIRS)
	rm -f ../$(so_file)
	rm -f ../$(pyi_file)
```