Extract city statistics via web APIs

We have following data sources:

1. OpenStreeMap city data from metro extracts.
2. Factual API: http://developer.factual.com/
3. AngelList API: https://angel.co/api

Python 3 is required. Addtional Python packages can be found in requirements.txt. To run the code, the machine need to have PostGIS and osm2pgsql. The code is only tested on Linux, i.e. wget and sudo are used to download OSM data and create postgres database.

Configurations are in extract.ini. Factual and AngelList API keys are needed.