How to use the psycopg2.Error function in psycopg2

def check_connection(params):
    delay = 0.01
    for _ in range(20):
        try:
            with psycopg2.connect(**params) as conn:
                with conn.cursor() as cursor:
                    cursor.execute('SELECT version();')
            break
        except psycopg2.Error:
            time.sleep(delay)
            delay *= 2
    else:
        pytest.fail('Cannot start postgres server')

cursor = connection.cursor()

    print("Executing Community Partner status inactive")


    update_k12_flag_for_existing_projects= """Update projects_project
                                                          Set k12_flag = 't' 
                                                          Where total_k12_students > 0 or total_k12_hours > 0;"""



    cursor.execute(update_k12_flag_for_existing_projects)
    connection.commit()

except (psycopg2.Error) as error:
    print("Error while connecting to Postgres SQL", error)

cursor.close()
connection.close()
print("Postgres SQL connection is closed")

url = asset.html_url
                        with self.env.cr.savepoint():
                            self.env['ir.attachment'].sudo().create(dict(
                                datas=base64.b64encode(asset.content.encode('utf8')),
                                mimetype='text/css',
                                type='binary',
                                name=url,
                                url=url,
                                datas_fname=fname,
                                res_model=False,
                                res_id=False,
                            ))

                        if self.env.context.get('commit_assetsbundle') is True:
                            self.env.cr.commit()
                    except psycopg2.Error:
                        pass

        return '\n'.join(asset.minify() for asset in self.stylesheets)

GROUP BY product_id, company_id, location_id, lot_id, package_id, owner_id, in_date
                            HAVING count(id) > 1
                        ),
                        _up AS (
                            UPDATE stock_quant q
                                SET quantity = d.quantity,
                                    reserved_quantity = d.reserved_quantity
                            FROM dupes d
                            WHERE d.to_update_quant_id = q.id
                        )
                   DELETE FROM stock_quant WHERE id in (SELECT unnest(to_delete_quant_ids) from dupes)
        """
        try:
            with self.env.cr.savepoint():
                self.env.cr.execute(query)
        except Error as e:
            _logger.info('an error occured while merging quants: %s', e.pgerror)

except (psycopg2.Error, psycopg2.Warning) as error:
            if fd in self._futures and not self._futures[fd].done():
                self._futures[fd].set_exception(error)
        else:
            if state == extensions.POLL_OK:
                if fd in self._futures and not self._futures[fd].done():
                    self._futures[fd].set_result(True)
            elif state == extensions.POLL_WRITE:
                self._ioloop.update_handler(fd, ioloop.IOLoop.WRITE)
            elif state == extensions.POLL_READ:
                self._ioloop.update_handler(fd, ioloop.IOLoop.READ)
            elif state == extensions.POLL_ERROR:
                self._ioloop.remove_handler(fd)
                if fd in self._futures and not self._futures[fd].done():
                    self._futures[fd].set_exception(
                        psycopg2.Error('Poll Error'))

self.dlg = EventDialog(self.iface.mainWindow(),
                               self.connection_wrapper_read,
                               self.connection_wrapper_write,
                               self.iface.mapCanvas(),
                               project_audit_table(),
                               replay_function=project_replay_function(),
                               table_map=table_map,
                               selected_layer_id=layer_id,
                               selected_feature_id=feature_id)

        # Populate dialog & catch error if any.
        try:
            self.dlg.populate()

        except Error as e:
            QMessageBox.critical(None, "Configuration problem",
                                 "Database configuration is invalid, please check the project configuration")
            r = self.onConfigure()

            # Retry if needed.
            if r == 1:
                self.connection_wrapper_read.closeConnection()
                self.connection_wrapper_write.closeConnection()
                self.onListEvents(layer_id, feature_id)

            return

        self.dlg.show()

variants_to_activate.write({'active': True})

            # create new product
            for variant_ids in to_create_variants:
                new_variant = Product.create({
                    'product_tmpl_id': tmpl_id.id,
                    'attribute_value_ids': [(6, 0, variant_ids.ids)]
                })

            # unlink or inactive product
            for variant in variants_to_unlink:
                try:
                    with self._cr.savepoint(), tools.mute_logger('odoo.sql_db'):
                        variant.unlink()
                # We catch all kind of exception to be sure that the operation doesn't fail.
                except (psycopg2.Error, except_orm):
                    variant.write({'active': False})
                    pass
        return True

def getColumnMinMaxAverage(baseQuery, colName):
    try:
        baseQuery = baseQuery.replace(";", " ")
        sql = "SELECT min(%s), max(%s), avg(%s) FROM (%s) baseQuery" % (colName, colName, colName, baseQuery)
        cur.execute(sql)
        record = cur.fetchone()
        return (record[0],record[1],record[2])
    except psycopg2.Error as e:
        pass
        return (-1,-1,-1)

def add(self, connection):
        """Add a new connection to the pool

        :param connection: The connection to add to the pool
        :type connection: psycopg2.extensions.connection
        :raises: PoolFullError

        """
        if id(connection) in self.connections:
            raise ValueError('Connection already exists in pool')

        if len(self.connections) == self.max_size:
            LOGGER.warning('Race condition found when adding new connection')
            try:
                connection.close()
            except (psycopg2.Error, psycopg2.Warning) as error:
                LOGGER.error('Error closing the conn that cant be used: %s',
                             error)
            raise PoolFullError(self)
        with self._lock:
            self.connections[id(connection)] = Connection(connection)
        LOGGER.debug('Pool %s added connection %s', self.id, id(connection))

def close(self):
        self.validate_thread_sharing()
        if self.connection is None:
            return

        try:
            self.pool.put(self.connection)
            self.connection = None
            #self.connection.close()
            #self.connection = None
        except Database.Error:
            # In some cases (database restart, network connection lost etc...)
            # the connection to the database is lost without giving Django a
            # notification. If we don't set self.connection to None, the error
            # will occur a every request.
            self.connection = None
            logger.warning('psycopg2 error while closing the connection.',
                exc_info=sys.exc_info()
            )
            raise