Why does stuff in pylib get compiled twice?

From: Hal Murray hmurray@megapathdsl.net

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[113/133] Compiling pylib/init.py

[114/133] Compiling pylib/init.py

[115/133] Compiling pylib/packet.py

[116/133] Compiling pylib/packet.py

[117/133] Compiling pylib/statfiles.py

[118/133] Compiling pylib/statfiles.py

[119/133] Compiling util/hist.c

[120/133] Compiling util/sht.c