code files included and their usage:
     count_tags.py: count tags
     count_users.py: count unique users
     audit.py: audit street name, update function included
     audit_city.py: audit city name, update function included
     audit_zip.py: audit postcode, update function included
     audit_state.py: audit state name, update function included
     audit_country.py: audit country name, update function included
     data_edit.py: the file for cleaning the osm data and transform osm file into json file

osm file included: 
     boston_massachusetts_sample.osm