How can i input the correct Timestamp corresponding to the time, when the data was retrieved in sqlite3?

I am modifying a code snippet from a udemy course, to fit my goal. My goal - > being able to store the timestamps in a sqlite3 database corresponding to the actual time the data was retrieved. The original code excerpt to update the database from the RaspberryPiFullStack_Raspbian github repository is given below;

def log_values(sensor_id, temp, hum): conn=sqlite3.connect('/var/www/lab_app/lab_app.db') #It is important to provide an #absolute path to the database #file, otherwise Cron won't be #able to find it! curs=conn.cursor() curs.execute("""INSERT INTO temperatures values(datetime(CURRENT_TIMESTAMP, 'localtime'), (?), (?))""", (sensor_id,temp)) curs.execute("""INSERT INTO humidities values(datetime(CURRENT_TIMESTAMP, 'localtime'), (?), (?))""", (sensor_id,hum)) conn.commit() conn.close() humidity, temperature = Adafruit_DHT.read_retry(Adafruit_DHT.AM2302, 17) temperature = temperature * 9/5.0 + 32 

As you can see, when the log_values function is called, only the instantaneous temperature and humidity value from the sensor, with the sqlite datetime function to timestamp when the reading was taken.

However, I have to process the values before i input them into the database. i have a function called "getAEEG(raw_data)", that accepts a list of raw data and returns a list of processed data. This function works fine independently. I have created an empty list for the temperature, humidity, and time that runs approximately for 10 seconds to store data onto the list. At the end of 10 seconds, i wish to store the values onto the database, with a for loop that iterates throughout the list to put them into the database. I have tried multiple iterations with no success, This is my first attempt coding in python and attempting to do projects with servers and databases, so i am reaching out to seek help diagnosing what's wrong with my code below.

t_data = [] ch1_data = [] ch2_data = [] ch1_aeeg = [] ch2_aeeg = [] def log_values(time_now,sensor_id, temp, hum): conn=sqlite3.connect('/var/www/lab_app/lab_app.db') #It is important to provide an #absolute path to the database #file, otherwise Cron won't be #able to find it! # For the time-related code (record timestamps and time-date calculations) to work # correctly, it is important to ensure that your Raspberry Pi is set to UTC. # This is done by default! # In general, servers are assumed to be in UTC. curs=conn.cursor() curs.execute("""INSERT INTO temperatures values((?), (?), (?))""", (time_now,sensor_id,temp)) curs.execute("""INSERT INTO humidities values((?), (?), (?))""", (time_now,sensor_id,hum)) conn.commit() conn.close() def getAEEG(raw_eeg): fs = 240.0 #typical sampling frequency for EEG f0 = 60.0 #freq to remove by notch Q = 30.0 #quality factor #notch filter to remove 60 Hz b_n, a_n = signal.iirnotch(f0/(fs/2), Q) notch_eeg = signal.lfilter(b_n, a_n, raw_eeg) #rectify eeg signal and convert V to uV rectify_eeg = abs(notch_eeg) #envelope filtered signal with low-pass 5th order Butterworth filter b,a = signal.butter(5, 0.021) envelope_eeg = signal.filtfilt(b,a, rectify_eeg) #aeeg output with added gain of 1.631 aeeg_output = 1.631*(envelope_eeg) return aeeg_output # setting up the 10 second condition for the while loop time_now_counter = datetime.datetime.now() tdelta = timedelta(seconds = +10) time_stop = time_now_counter + tdelta while time_now_counter < time_stop: time_now = datetime.datetime.now() t_data.append(time_now.strftime('%Y-%m-%d %H:%M:%S')) ch1_data.append(chan.voltage) ch2_data.append(random.randint(1,100)) time.sleep(0.5) time_now_counter = datetime.datetime.now() ch1_aeeg = getAEEG(ch1_data) ch2_aeeg = getAEEG(ch2_data) for x in range(len(ch1_aeeg)): time_now = t_data[x] temperature = ch1_aeeg[x] humidity = ch2_aeeg[x] log_values(time_now,"1", temperature, humidity) 

P.S. i also have scheduled a cron job, that is supposed to run the script every 15 seconds, since i thought that between two consecutive scheduled runs, the script will have to run for 10 seconds to get enough data with the remaing 5 seconds being buffer time.

is my rationale valid?