tracking down error in table merging in clean.py
tracking down error in table merging in clean.py

yngcan/patentprocessor,nikken1/patentprocessor,funginstitute/patentprocessor,funginstitute/patentprocessor,funginstitute/patentprocessor,yngcan/patentprocessor,nikken1/patentprocessor,nikken1/patentprocessor,yngcan/patentprocessor