Question: Is the release date of the film whose producer is Hal Roach prior to the year 1999?
Choices:
yes
no
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
Answer: yes
SPARQL: ASK { ?e <pred:instance_of> ?c . ?c <pred:name> "film" . ?e <producer> ?e_1 . ?e_1 <pred:name> "Hal Roach" .  ?e <publication_date> ?pv . ?pv <pred:year> ?v . FILTER ( ?v < 1999 ) .  }
Program:
function: Find
inputs: Hal Roach
function: Relate
dependencies: 0
inputs: producer
backward
function: FilterConcept
dependencies: 1
inputs: film
function: QueryAttr
dependencies: 2
inputs: publication date
function: VerifyYear
dependencies: 3
inputs: 1999
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