With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
To
confirm
this
hypothesis
,
it
is
required
to
take
an
optical
spectrum
of
the
white
dwarf
.
To:O
confirm:O
this:O
hypothesis:O
,:O
it:O
is:O
required:O
to:O
take:O
an:O
optical:O
spectrum:O
of:O
the:O
white:O
dwarf:O
.:O