from pprint import pprint as pp
import csv

csvstr1 = """data_files,name
72,Spengler
60,Julio Corl
28,Rae Divito
16,Guy Breau
33,Kurt Legros
81,Hugh Heras
 7,Agron
46,Hugh Kangas
65,Christian Legler
83,Kurt Nees
97,Alejandra Casazza
98,Nita Ostler
99,Clinton Wragg
67,Darren Lachowicz
"""
csvdata1 = list(csv.DictReader(csvstr1.splitlines()))

csvstr2 = """data_files,name
72,Melisa Ewin
 7,Lakisha Ebeling
46,Opperman
99,Tyrone Trezza
67,Dollie Railsback
"""
csvdata2 = list(csv.DictReader(csvstr2.splitlines()))

for d1 in csvdata1:
    for d2 in csvdata2:
        if d2["data_files"] == d1["data_files"]:
            d1["name"] = d2["name"]
            break
    else:
        print "{} not found.".format(d1["name"])

pp(csvdata1)