def __init__(self, block):
        """
        Create a fold-able region from a fold trigger block.

        :param block: The block **must** be a fold trigger.
        :type block: QTextBlock

        :raise: `ValueError` if the text block is not a fold trigger.
        """
        if not TextBlockHelper.is_fold_trigger(block):
            raise ValueError('Not a fold trigger')
        self._trigger = block
def __init__ ( self , block ) : if not TextBlockHelper . is_fold_trigger ( block ) : raise ValueError ( 'Not a fold trigger' ) self . _trigger = block
Create a fold-able region from a fold trigger block.

        :param block: The block **must** be a fold trigger.
        :type block: QTextBlock

        :raise: `ValueError` if the text block is not a fold trigger.