old_contents: from calcalcal.db import Event, DB
  
  def get_events(start, end):
      return DB.query(Event)\
          .filter_by(Event.date_start >= start)\
          .filter_by(Event.date_end <= end)
     
  
  def populate_data():
      Event(name='DesignPro')
      Event(name='Creative Skills')
      Event(name='Design & Thinking') 
new_contents: from calcalcal.db import Event, DBSEssion
  
  def get_events(start, end):
      return DBSEssion.query(Event)\
  		    .filter(Event.date_start >= start)\
  		    .filter(Event.date_end <= end)
        
     
  
  
subject: use the db session