code: func (c *Parser) ParseHeaders() error {
  	id, size, err := c.IDnSize()
  	if err != nil {
  		return err
  	}
  	c.ID = id
  	if c.ID != RiffID {
  		return fmt.Errorf("%s - %s", c.ID, ErrFmtNotSupported)
  	}
  	c.Size = size
  	if err := binary.Read(c.r, binary.BigEndian, &c.Format); err != nil {
  		return err
  	}
  
  	return nil
  }
docs: // ParseHeaders reads the header of the passed container and populat the container with parsed info.
  // Note that this code advances the container reader.