gistfile1.py

from collections import defaultdict

data = defaultdict(lambda: defaultdict(dict))
# populate the data structure
for row in table:
    data[row.make][row.model][row.lotnum] = color
# read the data structure
for make, models in data.items():
    for model, lots in models.items():
        for lotnum, color in lots.items():
            # do whatever