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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 modify(self, param_group=None, security_groups=None, preferred_maintenance_window=None, master_password=None, allocated_storage=None, instance_class=None, backup_retention_period=None, preferred_backup_window=None, multi_az=False, apply_immediately=False):
 """ Modify this DBInstance. :type security_groups: list of str or list of DBSecurityGroup objects :param security_groups: List of names of DBSecurityGroup to authorize on this DBInstance. :type preferred_maintenance_window: str :param preferred_maintenance_window: The weekly time range (in UTC) during which maintenance can occur. Default is Sun:05:00-Sun:09:00 :type master_password: str :param master_password: Password of master user for the DBInstance. Must be 4-15 alphanumeric characters. :type allocated_storage: int :param allocated_storage: The new allocated storage size, in GBs. Valid values are [5-1024] :type instance_class: str :param instance_class: The compute and memory capacity of the DBInstance. Changes will be applied at next maintenance window unless apply_immediately is True. Valid values are: * db.m1.small * db.m1.large * db.m1.xlarge * db.m2.xlarge * db.m2.2xlarge * db.m2.4xlarge :type apply_immediately: bool :param apply_immediately: If true, the modifications will be applied as soon as possible rather than waiting for the next preferred maintenance window. :type backup_retention_period: int :param backup_retention_period: The number of days for which automated backups are retained. Setting this to zero disables automated backups. :type preferred_backup_window: str :param preferred_backup_window: The daily time range during which automated backups are created (if enabled). Must be in h24:mi-hh24:mi format (UTC). :type multi_az: bool :param multi_az: If True, specifies the DB Instance will be deployed in multiple availability zones. :rtype: :class:`boto.rds.dbinstance.DBInstance` :return: The modified db instance. """

        return self.connection.modify_dbinstance(self.id,
                                                 param_group,
                                                 security_groups,
                                                 preferred_maintenance_window,
                                                 master_password,
                                                 allocated_storage,
                                                 instance_class,
                                                 backup_retention_period,
                                                 preferred_backup_window,
                                                 multi_az,
                                                 apply_immediately)