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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 stroke(self):
 """Property for strokes."""

        if not hasattr(self, '_stroke'):
            self._stroke = None
            stroke = self.tagged_blocks.get_data('VECTOR_STROKE_DATA')
            if stroke:
                self._stroke = Stroke(stroke)
        return self._stroke