text: import os
  from sqlalchemy.orm import sessionmaker
  from sqlalchemy.ext.declarative import declarative_base
  from sqlalchemy import create_engine, Column, Integer, String
  
  Base = declarative_base()
  Session = sessionmaker()
  
  engine = create_engine(
      os.environ.get("TPGROUTES_DATABASE_URL") or os.environ.get("DATABASE_URL")
  )
  Session.configure(bind=engine)
  session = Session()
  
  
  class MondayTimetables(Base):
      __tablename__ = "monday"
      id = Column(Integer, primary_key=True)
      departure_stop = Column(String)
      arrival_stop = Column(Integer)
      departure_time = Column(Integer)
      arrival_time = Column(Integer)
      line = Column(String)
      trip_id = Column(Integer)
      destination_stop = Column(Integer)
  
      def __str__(self):
          return f"{self.departure_stop} / {self.arrival_stop} / {self.departure_time} / {self.arrival_time} / {self.line} / {self.trip_id} / {self.destination_stop}"
  
  
  class FridayTimetables(Base):
      __tablename__ = "friday"
      id = Column(Integer, primary_key=True)
      departure_stop = Column(String)
      arrival_stop = Column(Integer)
      departure_time = Column(Integer)
      arrival_time = Column(Integer)
      line = Column(String)
      trip_id = Column(Integer)
      destination_stop = Column(Integer)
  
      def __str__(self):
          return f"{self.departure_stop} / {self.arrival_stop} / {self.departure_time} / {self.arrival_time} / {self.line} / {self.trip_id} / {self.destination_stop}"
  
  
  class SaturdayTimetables(Base):
      __tablename__ = "saturday"
      id = Column(Integer, primary_key=True)
      departure_stop = Column(String)
      arrival_stop = Column(Integer)
      departure_time = Column(Integer)
      arrival_time = Column(Integer)
      line = Column(String)
      trip_id = Column(Integer)
      destination_stop = Column(Integer)
  
      def __str__(self):
          return f"{self.departure_stop} / {self.arrival_stop} / {self.departure_time} / {self.arrival_time} / {self.line} / {self.trip_id} / {self.destination_stop}"
  
  
  class SundayTimetables(Base):
      __tablename__ = "sunday"
      id = Column(Integer, primary_key=True)
      departure_stop = Column(String)
      arrival_stop = Column(Integer)
      departure_time = Column(Integer)
      arrival_time = Column(Integer)
      line = Column(String)
      trip_id = Column(Integer)
      destination_stop = Column(Integer)
  
      def __str__(self):
          return f"{self.departure_stop} / {self.arrival_stop} / {self.departure_time} / {self.arrival_time} / {self.line} / {self.trip_id} / {self.destination_stop}"
  