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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def unfold(self):
 """Unfolds the region."""

        # set all direct child blocks which are not triggers to be visible
        self._trigger.setVisible(True)
        TextBlockHelper.set_collapsed(self._trigger, False)
        for block in self.blocks(ignore_blank_lines=False):
            block.setVisible(True)
            if TextBlockHelper.is_fold_trigger(block):
                TextBlockHelper.set_collapsed(block, False)