<snapdata remixID="8923452"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"><notes></notes><thumbnail>data:image/png;base64,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</thumbnail><stage name="Stage" width="480" height="360" costume="0" color="255,255,255,1" tempo="60" threadsafe="false" volume="100" pan="0" lines="flat" ternary="true" codify="false" inheritance="false" sublistIDs="false" scheduled="false" id="1"><pentrails>data:image/png;base64,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