code: def write(self, fn=None):
          
          fn = fn or self.fn
          if not os.path.exists(os.path.dirname(fn)):
              os.makedirs(os.path.dirname(fn))
          f = open(self.fn, 'rb')
          b = f.read()
          f.close()
          f = open(fn, 'wb')
          f.write(b)
          f.close()
docs: copy the zip file from its filename to the given filename.