input: Write a function to set up GPIO pins, import necessary modules, define operating modes, prompt for password and mode selection, check license validity and user registration, calculate BAC, open solenoid to dispense beer if valid license and BAC below threshold, and record swipe data in appropriate file. The function should return True if the beer is dispensed and False otherwise.
  
  def beer_dispenser():
      from time import sleep
      import RPi.GPIO as GPIO
      GPIO.setmode(GPIO.BOARD)
      GPIO.setwarnings(False)
      GPIO.setup(3, GPIO.OUT)
      GPIO.setup(3, GPIO.LOW)
      from CheckLicense import check_license, calc_BAC
      import getpass
      import sys
      import re
      while True:
          mode_req = input("Enter Mode(normal, party, barkeep): ")
          if mode_req in ["normal", "party", "barkeep"]:
              passwd = getpass.getpass("Enter password: ")
              if passwd == "admin":
                  mode = mode_req
                  break
      while mode == 'normal':
          raw_text = getpass.getpass('Swipe card now:   ').strip()
          check_license_out = check_license(raw_text)
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          DL_num = check_license_out[3]
          users = open("users_list.txt", 'r')
          hit = 0
          if valid_license == 'Yes':
              for line in users:
                  if re.search(DL_num, line, re.IGNORECASE):
                      hit += 1
              if hit < 1:
                  valid_license = 'No'
          BAC = calc_BAC(raw_text)
          if valid_license == 'Yes':
              GPIO.setup(3, GPIO.HIGH)
              sleep(2)
              GPIO.setup(3, GPIO.LOW)
              with open("swipes.txt", "a") as myfile:
                  myfile.write(last_name + "," + first_name + " " + DL_num + " " + mode + " " + time.strftime("%Y-%m-%d") + " " + str(time.time()) + "\n")
              return True
          else:
              return False
      while mode == "party":
          raw_license_text = getpass.getpass('Swipe card now:   ').strip()
          check_license_out = check_license(raw_license_text)
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          if valid_license == 'Yes':
              GPIO.setup(3, GPIO.HIGH)
              sleep(2)
              GPIO.setup(3, GPIO.LOW)
              with open("swipes_normal.txt", "a") as myfile:
                  myfile.write(last_name + "," + first_name + "," + time.strftime("%Y%m%d%H%M%S\n"))
              return True
          else:
              return False
      while mode == "barkeep":
          check_license_out = check_license(getpass.getpass('Swipe card now:   ').strip())
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          blacklist = open("blacklist.txt", 'r')
          hit = 0
          if valid_license == 'Yes':
              for line in blacklist:
                  if re.search(last_name, line, re.IGNORECASE):
                      hit += 1
                  if re.search(first_name, line, re.IGNORECASE):
                      hit += 1
              if hit >= 2:
                  blacklisted = 'Yes'
              else:
                  blacklisted = 'No'
          if blacklisted == 'No':
              BAC = calc_BAC(raw_text)
              if BAC < intoxicated:
                  GPIO.setup(3, GPIO.HIGH)
                  sleep(2)
                  GPIO.setup(3, GPIO.LOW)
                  with open("swipes_barkeep.txt", "a") as myfile:
                      myfile.write(last_name + "," + first_name + "_" + time.strftime("%Y-%m-%d %H:%M%S\n"))
                  return True
              else:
                  return False
          else:
              return False
  
  assert beer_dispenser() == True
  assert beer_dispenser() == False
output: 
  def beer_dispenser():
      from time import sleep
      import RPi.GPIO as GPIO
      GPIO.setmode(GPIO.BOARD)
      GPIO.setwarnings(False)
      GPIO.setup(3, GPIO.OUT)
      GPIO.setup(3, GPIO.LOW)
      from CheckLicense import check_license, calc_BAC
      import getpass
      import sys
      import re
      while True:
          mode_req = input("Enter Mode(normal, party, barkeep): ")
          if mode_req in ["normal", "party", "barkeep"]:
              passwd = getpass.getpass("Enter password: ")
              if passwd == "admin":
                  mode = mode_req
                  break
      while mode == 'normal':
          raw_text = getpass.getpass('Swipe card now:   ').strip()
          check_license_out = check_license(raw_text)
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          DL_num = check_license_out[3]
          users = open("users_list.txt", 'r')
          hit = 0
          if valid_license == 'Yes':
              for line in users:
                  if re.search(DL_num, line, re.IGNORECASE):
                      hit += 1
              if hit < 1:
                  valid_license = 'No'
          BAC = calc_BAC(raw_text)
          if valid_license == 'Yes':
              GPIO.setup(3, GPIO.HIGH)
              sleep(2)
              GPIO.setup(3, GPIO.LOW)
              with open("swipes.txt", "a") as myfile:
                  myfile.write(last_name + "," + first_name + " " + DL_num + " " + mode + " " + time.strftime("%Y-%m-%d") + " " + str(time.time()) + "\n")
              return True
          else:
              return False
      while mode == "party":
          raw_license_text = getpass.getpass('Swipe card now:   ').strip()
          check_license_out = check_license(raw_license_text)
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          if valid_license == 'Yes':
              GPIO.setup(3, GPIO.HIGH)
              sleep(2)
              GPIO.setup(3, GPIO.LOW)
              with open("swipes_normal.txt", "a") as myfile:
                  myfile.write(last_name + "," + first_name + "," + time.strftime("%Y%m%d%H%M%S\n"))
              return True
          else:
              return False
      while mode == "barkeep":
          check_license_out = check_license(getpass.getpass('Swipe card now:   ').strip())
          valid_license = check_license_out[0]
          first_name = check_license_out[1]
          last_name = check_license_out[2]
          blacklist = open("blacklist.txt", 'r')
          hit = 0
          if valid_license == 'Yes':
              for line in blacklist:
                  if re.search(last_name, line, re.IGNORECASE):
                      hit += 1
                  if re.search(first_name, line, re.IGNORECASE):
                      hit += 1
              if hit >= 2:
                  blacklisted = 'Yes'
              else:
                  blacklisted = 'No'
          if blacklisted == 'No':
              BAC = calc_BAC(raw_text)
              if BAC < intoxicated:
                  GPIO.setup(3, GPIO.HIGH)
                  sleep(2)
                  GPIO.setup(3, GPIO.LOW)
                  with open("swipes_barkeep.txt", "a") as myfile:
                      myfile.write(last_name + "," + first_name + "_" + time.strftime("%Y-%m-%d %H:%M%S\n"))
                  return True
              else:
                  return False
          else:
              return False
  