what is the {start time} for {Luigi Cherubini} has {position held} as {directors of higher national conservatories of music, dance and drama in France} ?
On what date(s) did Luigi Cherubini become the director of the French higher national conservatories of music, dance, and drama?
When did Luigi Cherubini start holding the position as directors of higher national conservatories of music, dance and drama in France?
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