Hardware components:

• Raspberry Pi 3
• DHT11 Temperature and Humidity Sensor [1] (I use DHT11 because this is what I have now. Also, it’s good enough for my environment – 0 ~ 40 degrees Celsius.)

Pin 1: Output
Pin 2: VCC
Pin 3: GND

• SainSmart LCD Module For Arduino 20 X 4 [2]

Pin 1 : GND
Pin 2 : 5V
Pin 3 : Contrast (0-5V)
Pin 4 : RS (Register Select)
Pin 5 : R/W (Read Write)
Pin 6 : Enable or Strobe
Pin 7 : Data Bit 0
Pin 8 : Data Bit 1
Pin 9 : Data Bit 2
Pin 10: Data Bit 3
Pin 11: Data Bit 4
Pin 12: Data Bit 5
Pin 13: Data Bit 6
Pin 14: Data Bit 7
Pin 15: LCD Backlight +5V**
Pin 16: LCD Backlight GND

Reference site:
https://www.hackster.io/porrey/dht11-dht22-temperature-sensor-077790

http://www.circuitbasics.com/how-to-set-up-the-dht11-humidity-sensor-on-the-raspberry-pi/

Code:
(Reference: [3])

#!/usr/bin/python

import RPi.GPIO as GPIO
import time
import socket
import fcntl
import struct
import logging
import Adafruit_DHT

# Define GPIO to LCD mapping
LCD_RS = 7
LCD_E  = 8
LCD_D4 = 25
LCD_D5 = 24
LCD_D6 = 23
LCD_D7 = 18
LED_ON = 15
 
# Define some device constants
LCD_WIDTH = 20    # Maximum characters per line
LCD_CHR = True
LCD_CMD = False
 
LCD_LINE_1 = 0x80 # LCD RAM address for the 1st line
LCD_LINE_2 = 0xC0 # LCD RAM address for the 2nd line
LCD_LINE_3 = 0x94 # LCD RAM address for the 3rd line
LCD_LINE_4 = 0xD4 # LCD RAM address for the 4th line
 
# Timing constants
E_PULSE = 0.0005
E_DELAY = 0.0005
 
def main():
  # Main program block
  logging.basicConfig(filename='/home/cywang/sensor.log', format='%(asctime)s %(message)s', level=logging.DEBUG, datefmt='%Y.%m.%d %I:%M:%S')

  logging.debug("Start temperature and humidity monitor")
 
  GPIO.setmode(GPIO.BCM)       # Use BCM GPIO numbers
  GPIO.setup(LCD_E, GPIO.OUT)  # E
  GPIO.setup(LCD_RS, GPIO.OUT) # RS
  GPIO.setup(LCD_D4, GPIO.OUT) # DB4
  GPIO.setup(LCD_D5, GPIO.OUT) # DB5
  GPIO.setup(LCD_D6, GPIO.OUT) # DB6
  GPIO.setup(LCD_D7, GPIO.OUT) # DB7

 
  # Initialise display
  logging.debug("Initialize LCD")
  lcd_init()
 

  logging.debug("Retrieving IP address")
  hasIp = False
  retry = 3
  while hasIp != True and retry > 0:
    lanIp = get_ip_address('enxb827eb936cc3')
    wirelessIp = get_ip_address('wlan0')
    if lanIp != 'N/A':
      lcd_string("LAN IP",LCD_LINE_1,1)
      lcd_string(lanIp,LCD_LINE_2,1)
      hasIp = True
    elif wirelessIp != 'N/A':
      lcd_string("Wireless IP",LCD_LINE_1,1)
      lcd_string(wirelessIp,LCD_LINE_2,1)
      hasIp = True
    else:
      lcd_string("IP Address",LCD_LINE_1,1)
      lcd_string("    N'A" ,LCD_LINE_2,1)
      retry = retry - 1
      logging.debug('Retry time: {0:d}'.format(3 - retry))
      time.sleep(60) 

  logging.debug("Monitoring temperature and humidity...")
  lcd_string("Temperature/Humidity",LCD_LINE_3,1)
  while True:
    sensor_data = get_temperature_and_humidity()
    lcd_string(sensor_data,LCD_LINE_4,1)
    #logging.debug(sensor_data)
    #print sensor_data
    time.sleep(10) 

def get_temperature_and_humidity():
  sensor = Adafruit_DHT.DHT11
  pin = 4

  try:
    humidity, temperature = Adafruit_DHT.read_retry(sensor, pin)
    if humidity is not None and temperature is not None:
      deg = u'\xb0'
      logging.debug('Temperature: {0:0.1f} {1:s}C - Humidity: {2:0.1f}%'.format(temperature, deg.encode('utf8'), humidity))
      return '{0:0.1f} C / {1:0.1f}%'.format(temperature, humidity)
    else:
      return "Failed to get temperature/humidity"
  except:
      return "Failed to get temperature/humidity"

def get_ip_address(ifname):
  try:
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    return socket.inet_ntoa(fcntl.ioctl(
      s.fileno(),
      0x8915,  # SIOCGIFADDR
      struct.pack('256s', ifname[:15])
    )[20:24])
  except:
    return "N/A"
 
def lcd_init():
  # Initialise display
  lcd_byte(0x33,LCD_CMD) # 110011 Initialise
  lcd_byte(0x32,LCD_CMD) # 110010 Initialise
  lcd_byte(0x06,LCD_CMD) # 000110 Cursor move direction
  lcd_byte(0x0C,LCD_CMD) # 001100 Display On,Cursor Off, Blink Off
  lcd_byte(0x28,LCD_CMD) # 101000 Data length, number of lines, font size
  lcd_byte(0x01,LCD_CMD) # 000001 Clear display
  time.sleep(E_DELAY)
 
def lcd_byte(bits, mode):
  # Send byte to data pins
  # bits = data
  # mode = True  for character
  #        False for command
 
  GPIO.output(LCD_RS, mode) # RS
 
  # High bits
  GPIO.output(LCD_D4, False)
  GPIO.output(LCD_D5, False)
  GPIO.output(LCD_D6, False)
  GPIO.output(LCD_D7, False)
  if bits&0x10==0x10:
    GPIO.output(LCD_D4, True)
  if bits&0x20==0x20:
    GPIO.output(LCD_D5, True)
  if bits&0x40==0x40:
    GPIO.output(LCD_D6, True)
  if bits&0x80==0x80:
    GPIO.output(LCD_D7, True)
 
  # Toggle 'Enable' pin
  lcd_toggle_enable()
 
  # Low bits
  GPIO.output(LCD_D4, False)
  GPIO.output(LCD_D5, False)
  GPIO.output(LCD_D6, False)
  GPIO.output(LCD_D7, False)
  if bits&0x01==0x01:
    GPIO.output(LCD_D4, True)
  if bits&0x02==0x02:
    GPIO.output(LCD_D5, True)
  if bits&0x04==0x04:
    GPIO.output(LCD_D6, True)
  if bits&0x08==0x08:
    GPIO.output(LCD_D7, True)
 
  # Toggle 'Enable' pin
  lcd_toggle_enable()
 
def lcd_toggle_enable():
  # Toggle enable
  time.sleep(E_DELAY)
  GPIO.output(LCD_E, True)
  time.sleep(E_PULSE)
  GPIO.output(LCD_E, False)
  time.sleep(E_DELAY)
 
def lcd_string(message,line,style):

  if style==1:
    message = message.ljust(LCD_WIDTH," ")
  elif style==2:
    message = message.center(LCD_WIDTH," ")
  elif style==3:
    message = message.rjust(LCD_WIDTH," ")
 
  lcd_byte(line, LCD_CMD)
 
  for i in range(LCD_WIDTH):
    lcd_byte(ord(message[i]),LCD_CHR)
 
def lcd_backlight(flag):
  GPIO.output(LED_ON, flag)
 
if __name__ == '__main__':
  main()
  logging.debug("Exit")

[1] Elegoo EL-KIT-000 37-in-1 Sensor Module Kit: Amazon Link

[2] SainSmart LCD Module For Arduino 20 X 4: Amazon Link

[3] https://github.com/brantje/rpi-16×2-lcd/blob/master/lcd.py