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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 blocks_to_mark_complete_on_view(self, blocks):
 """ Returns a set of blocks which should be marked complete on view and haven't been yet. """

        blocks = {block for block in blocks if self.can_mark_block_complete_on_view(block)}
        completions = self.get_completions({block.location for block in blocks})
        return {block for block in blocks if completions.get(block.location, 0) < 1.0}