With no explanation, label each line with "O", "person-artist/author", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
concert
's
musical
directors
were
Don
Was
and
Helm
's
frequent
collaborator
Larry
Campbell
.
The:O
concert:O
's:O
musical:O
directors:O
were:O
Don:person-artist/author
Was:person-artist/author
and:O
Helm:O
's:O
frequent:O
collaborator:O
Larry:person-artist/author
Campbell:person-artist/author
.:O