OpenData Sources
https://www.quandl.com/
https://www.openml.org/search?type=data
Sources for large CSV files
https://www.openml.org/search?type=data&sort=qualities.NumberOfInstances&order=desc
https://data.gov.uk/dataset/4c9b7641-cf73-4fd9-869a-4bfeed6d440e/hm-land-registry-price-paid-data
