EWS_RaspberryPi

import RPi.GPIO as GPIO
import dht11
import time
import datetime
import MySQLdb

# initialize GPIO
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BCM)

# read data using pin 14 from DHT11
dhtSensor = dht11.DHT11(pin=14)
GPIO.setup(16,GPIO.OUT)

#Set Threshold for warning message
def THRESHOLD():
    return 20

class ultrasonicSensor:
    TRIG = 20
    ECHO = 21
    def __init__(self):
        GPIO.setmode(GPIO.BCM)
        GPIO.setwarnings(False)
        GPIO.setup(self.TRIG,GPIO.OUT)
        GPIO.setup(self.ECHO,GPIO.IN)

    def readData(self):
        pulse_start=0;
        pulse_end=0;

        GPIO.output(self.TRIG, False)
        time.sleep(2)
        GPIO.output(self.TRIG, True)
        time.sleep(0.00001)
        GPIO.output(self.TRIG, False)

        while GPIO.input(self.ECHO)==0:
            pulse_start = time.time()
        while GPIO.input(self.ECHO)==1:
            pulse_end = time.time()

        pulse_duration = pulse_end - pulse_start
        distance = pulse_duration * 17150
        distance = round(distance, 2)
        time.sleep(0.4)
        return distance;

ultrasonicSensorObj=ultrasonicSensor();
while True:
    remarks_val="Nothing to Worry"
    dhtSensorValue = dhtSensor.read()
    waterLevel=1000-ultrasonicSensorObj.readData();
    dateandtime=datetime.datetime.now()
    if dhtSensorValue.is_valid():
        print"----------------------------------------------------"
        print("Time: " + dateandtime)
        print("Temperature: %-3.1f C" % dhtSensorValue.temperature)
        print("Humidity: %-3.1f %%" % dhtSensorValue.humidity)
        print "WaterLevel:",waterLevel,"cm"
        time.sleep(3)
        print"----------------------------------------------------"
    if(waterLevel<=THRESHOLD()):
        GPIO.output(16,GPIO.HIGH)
        print "WARNING!!! THE LEVEL OF WATER HAS RAISED BEYOND THE THRESHOLD LEVEL"
        remarks_val="WARNING!!! THE LEVEL OF WATER HAS RAISED BEYOND THE THRESHOLD LEVEL"
    else:
        GPIO.output(16,GPIO.LOW)
        print"----------------------------------------------------"

    conn=MySQLdb.connect(host="localhost",user="YOURUSERNAME",passwd="YOURPASSWORD",db="YOURDATABASE")
    cur=conn.cursor()
    sql_query="""INSERT INTO Data (DateTime,Temperature,Humidity,WaterLevel,Remarks) VALUES (%s,%s,%s,%s,%s)"""
    cur.execute(sql_query,(dateandtime,dhtSensorValue.temperature,dhtSensorValue.humidity,waterLevel,remarks_val))
    conn.commit()
    conn.close()