import csv

name = '__tu_meno_suboru__.csv'

with open(name, newline='') as f:
    my_csv = [row for row in csv.reader(f)]

my_word_set = set(row[1] for row in my_csv)
my_dict = {word: input('Zadaj preklad pre "%s": ' % word) for word in my_word_set}

with open(name, 'w', newline='') as f:
    csv_writer = csv.writer(f)
    for row in my_csv:
        csv_writer.writerow(([row[0], row[1], my_dict[row[1]]] for row in my_csv))