id, prod_name
1, apple
2, cherry
id, src
1, http://link_1
5, http://link_5
id, prod_name, src
1, apple, http://link_1
from csv import reader
d = dict(reader(open('Первый.csv')))
for id, src in (reader(open('Второй.csv'))):
if id in d:
print(id, d[id], src)