'Returns the list of visible blocks.
Each element in the list is a tuple made up of the line top position,
the line number (already 1 based), and the QTextBlock itself.
:return: A list of tuple(top position, line number, block)
:rtype: List of tuple(int, int, QtGui.QTextBlock)'

@property
def visible_blocks(self):

    return self.__visible_blocks
