Why does the getinventory() and other methods not exist in the Player.php on the source code?

developing a plugin and when i went to the source code to look for why it isnt showing up and it was not there. i thought it was my ide but nope it truly does not exist, i want to know as to why that is and what other methods have been removed from it, atleast in the source code...

 

http://php.net/manual/en/language.oop5.inheritance.php

 

class Player.php does not seem to inherit anything that has that method....

 

Nvm, fixed it , i guess i didnt look deep enough, found the Living.php , thats where its inherited from. Thx