What is the purpose of using the keyword "self" throughout the declaration of the phone class?

class phone:

def selnit$\_($self$,$ finish, width, height, depth, weig

self, finish $=$ finish

self.width $=$ width

self. height $=$ height

self.depth $=$ depth

self.weight $=$ weight

iPhone$11$Pro $=$ phone$("$Space Gray",$2\mathrm{.}81,5\mathrm{.}67,0\mathrm{.}32,6\mathrm{.}63)$

print $($iPhone$11$Pro.finish$)$

iPhone$11$Pro.finish $=$ "Gold"

rint $($iPhone$11$Pro.finish$)$