code: def get_bytes(self, n):
          
          b = self.packet.read(n)
          if len(b) < n:
              return b + '\x00' * (n - len(b))
          return b
docs: Return the next C{n} bytes of the Message, without decomposing into
          an int, string, etc.  Just the raw bytes are returned.
  
          @return: a string of the next C{n} bytes of the Message, or a string
              of C{n} zero bytes, if there aren't C{n} bytes remaining.
          @rtype: string