With no explanation, label each line with "O", "other-chemicalthing", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Black
cocaine
(
)
is
a
mixture
of
regular
cocaine
base
or
cocaine
hydrochloride
with
various
other
substances
.
Black:other-chemicalthing
cocaine:other-chemicalthing
(:O
):O
is:O
a:O
mixture:O
of:O
regular:O
cocaine:other-chemicalthing
base:other-chemicalthing
or:O
cocaine:other-chemicalthing
hydrochloride:other-chemicalthing
with:O
various:O
other:O
substances:O
.:O