def get_completed_exploration_ids(user_id, collection_id):
 progress_model = user_models.CollectionProgressModel.get(user_id, collection_id)
 return (progress_model.completed_explorations if progress_model else [])

def get_completed_exploration_ids ( user_id , collection_id ) : progress_model = user_models . CollectionProgressModel . get ( user_id , collection_id ) return ( progress_model . completed_explorations if progress_model else [ ] )
returns a list of explorations the user has completed within the context of the provided collection .