def merge(sound1,sound2):
  
  target= makeEmptySound(6*44100)
  #target = makeSound(getMediaPath("sec3silence.wav"))
  index = 0
  for source in range(0, getLength(sound1)):
    value = getSampleValueAt(sound1, source)
    setSampleValueAt(target, index, value)
    index = index + 1
    
  for source in range(0, int(0.2*getSamplingRate(target))):
    setSampleValueAt(target, index, 0)
    index = index + 1
  
  for source in range(0, getLength(sound2)):
    value = getSampleValueAt(sound2, source)
    setSampleValueAt(target, index, value)
    index = index + 1
  
  return target

def main():
  file = pickAFile()
  sound1 = makeSound(file) 
  file= pickAFile()
  sound2= makeSound(file)
  sound3= merge(sound1,sound2)
  explore( sound3) 
  writeSoundTo(sound3,"/Users/bilal/Desktop/sound3.wav")