code: def was_modified_since(header=None, mtime=0, size=0):
      '''Check if an item was modified since the user last downloaded it
  
      :param header: the value of the ``If-Modified-Since`` header.
          If this is ``None``, simply return ``True``
      :param mtime: the modification time of the item in question.
      :param size: the size of the item.
      '''
      header_mtime = modified_since(header, size)
      if header_mtime and header_mtime <= mtime:
          return False
      return Truf was_modified_since(header=None, mtime=0, size=0):
      '''Check if an item was modified since the user last downloaded it
  
      :param header: the value of the ``If-Modified-Since`` header.
          If this is ``None``, simply return ``True``
      :param mtime: the modification time of the item in question.
      :param size: the size of the item.
      '''
      header_mtime = modified_since(header, size)
      if header_mtime and header_mtime <= mtime:
          return False
      return True
docs: Check if an item was modified since the user last downloaded it
  
      :param header: the value of the ``If-Modified-Since`` header.
          If this is ``None``, simply return ``True``
      :param mtime: the modification time of the item in question.
      :param size: the size of the item.