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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def db_connect(engine, schema=None, clobber=False):
 """Create a connection object to a database. Attempt to establish a schema. If there are existing tables, delete them if clobber is True and return otherwise. Returns a sqlalchemy engine object. """


    if schema is None:
        base = declarative_base()
    else:
        try:
            engine.execute(sqlalchemy.schema.CreateSchema(schema))
        except sqlalchemy.exc.ProgrammingError as err:
            logging.warn(err)
        base = declarative_base(metadata=MetaData(schema=schema))

    define_schema(base)

    if clobber:
        logging.info('Clobbering database tables')
        base.metadata.drop_all(bind=engine)

    logging.info('Creating database tables')
    base.metadata.create_all(bind=engine)

    return base