old_contents: #!/usr/bin/env python
  import os
  import sys
  
  def exit_if_user_run_this_script_as_general_user():
      if not os.getuid() == 0:
          print 'Error: You need root permission to run this script.'
          sys.exit(os.EX_NOPERM)
  
  if __name__ == '__main__':
      exit_if_user_run_this_script_as_general_user()
  
new_contents: #!/usr/bin/env python
  import os
  import sys
  
  from scapy.all import *
  
  def exit_if_user_run_this_script_as_general_user():
      if not os.getuid() == 0:
          print 'Error: You need root permission to run this script.'
          sys.exit(os.EX_NOPERM)
  
  def sniff_found_dash_button(packet):
      arp_packet = packet[ARP]
      print 'Please push dash button'
  
      if arp_packet.op == 1:
          if arp_packet.hwdst == '00:00:00:00:00:00':
              print 'Dash button found!'
              print 'MAC Address of Dash button:' + arp_packet.hwsrc
              sys.exit(0)
  
  def found_dash_button():
      print sniff(prn=sniff_found_dash_button, filter="arp", store=0, count=10)
  
  if __name__ == '__main__':
      exit_if_user_run_this_script_as_general_user()
  
subject: Add functions: found_dash_button(), sniff_found_dasu_button()