base_str = ''.join(random.choice(string.ascii_lowercase) for i in range(100000000)) start_time = time.time() durations = [] dictionary = {} for i in range(26): dictionary[string.ascii_lowercase[i]] = i start_time = time.time() result = [] for c in base_str: result.append(dictionary[c]) durations.append(time.time() - start_time) start_time = time.time() result = [] for c in base_str: result.append(ord(c)-97) durations.append(time.time() - start_time) print(durations)