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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 iter_block_items(self):
 """ Generate a reference to each of the block-level content elements in this cell, in the order they appear. """

        block_item_tags = (qn('w:p'), qn('w:tbl'), qn('w:sdt'))
        for child in self:
            if child.tag in block_item_tags:
                yield child