code: def tree_is_in_collection(collection, study_id=None, tree_id=None):
      
      included = collection_to_included_trees(collection)
      study_id = study_id.strip()
      tree_id = tree_id.strip()
      for decision in included:
          if decision['studyID'] == study_id and decision['treeID'] == tree_id:
              return True
      return False
docs: Takes a collection object (or a filepath to collection object), returns
      True if it includes a decision to include the specified tree