old_contents: from tinydb import TinyDB
  from tinydb import where
  
  class Brain(object):
      def __init__(self, db_location):
          self.db = TinyDB(db_location)
  
new_contents: from tinydb import TinyDB
  
  class Brain(object):
      def __init__(self, db_location):
          self.db = TinyDB(db_location)
  
subject: Remove unused import from brain.py