code: def advance(self, blocksize):
          
          ts = self._read_frame(blocksize)
  
          self.raw_buffer.roll(-len(ts))
          self.raw_buffer[-len(ts):] = ts[:]
          self.read_pos += blocksize
          self.raw_buffer.start_time += blocksize
          return ts
docs: Add blocksize seconds more to the buffer, push blocksize seconds
          from the beginning.
  
          Parameters
          ----------
          blocksize: int
              The number of seconds to attempt to read from the channel