code: def convert_to_dimension(d):
    
    if d is None:
      return None
    if isinstance(d, Dimension):
      if not isinstance(d.name, str) or not isinstance(d.size, int):
        raise ValueError("Bad dimension %s" % (d,))
      return d
    name, size = d
    if isinstance(name, str) and isinstance(size, int):
      return Dimension(name, size)
    else:
      raise ValueError("could not convert %s to Dimension" % (d,))
docs: Converts input to a Dimension.
  
    Args:
      d: Dimension, tuple (string, int), or None.
  
    Returns:
      Dimension or None.
  
    Raises:
      ValueError: If d cannot be converted to a Dimension.