Route influence (or) How to change BGP Attribute?

Simulation scenario: Any routes coming from AS500, set weight to 4000

Router(config)# ip as-path access-list 99 permit _500_
Router(config)#
Router(config)# route-map INFLUENCE seq 10
Router(config)# match as-path 99
Router(config)# set weight 4000 ( instant of "weight", we can set other BGP attributes)
Router(config)#
Router(config)# route-map INFLUENCE seq 20
Router(config)# exit
Router(config)#
Router(config)# router bgp 100
Router(config)# neighbor 1.1.1.1 remote-as 200
Router(config)# neighbor 1.1.1.1 route-map INFLUENCE in
Router(config)# exit
Router(config)# clear ip bgp 1.1.1.1 (reset the neighbor relationship)

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route-map structure is similar to If \ Then statement (from programming)
> route-map NAME
> If (the statement is true)
> Then ( Action / Do This)

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