Download Dynamsoft Barcode Reader SDK v7.2.2 for Raspberry Pi.

Copy libDynamsoftBarcodeReader.so to /usr/lib. If you don't have access to /usr/lib, try to copy the library to /usr/local/lib and set the LD_LIBRARY_PATH as follows:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

Build and install the Python extension:

cd src
sudo python setup.py build install