With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
After
looping
around
the
Darwin
area
overnight
and
back
over
land
the
system
weakened
on
17
February
and
BOM
downgraded
it
to
a
Tropical
low
.
After:O
looping:O
around:O
the:O
Darwin:location-GPE
area:O
overnight:O
and:O
back:O
over:O
land:O
the:O
system:O
weakened:O
on:O
17:O
February:O
and:O
BOM:O
downgraded:O
it:O
to:O
a:O
Tropical:O
low:O
.:O