Read two column CSV as dict with 1st column as key

Question

I have a CSV with two columns, column one is the team dedicated to a particular building in our project.

The second column is the actual building number.

Wha

Answer 1

The useful collections.defaultdict in the standard library makes short work of this task:

import csv
import collections as co

dd = co.defaultdict(list)
with open('/path/to/your.csv'),'rb') as fin:
    dr = csv.DictReader(fin)
    for line in dr:
        dd[line['team']].append(line['bldg'])

# defaultdict(, {'1': ['1450'], '3': ['204', '250', '1437'], '2': ['1440']})

http://docs.python.org/2/library/collections.html#collections.defaultdict

The first argument provides the initial value for the default_factory attribute; it defaults to None.