new_contents: #!/usr/bin/env python2.7
  import sys, serial, struct
  port = '/dev/ttyACM0'
  sp = serial.Serial(port, baudrate=115200, bytesize=serial.EIGHTBITS, parity=serial.PARITY_NONE,
              xonxoff=False, rtscts=False, stopbits=serial.STOPBITS_ONE, timeout=None, dsrdtr=True)
  sp.setDTR(True) # dsrdtr is ignored on Windows.
  sp.write("snap")
  sp.flush()
  size = struct.unpack('<L', sp.read(4))[0]
  img = sp.read(size)
  sp.close()
  
  with open("img.jpg", "w") as f:
      f.write(img)
  
subject: Add USB VCP test script.