x=+1 is treated as: x=(+1)
while x+=1 is treated as: x=x+1
There are binary operators which operates on their left-handside operand and their right-hand side operand (e.g. * multiplication).
And there are unary operators which takes only right-hand side operand (e.g. ~/! negation).
There are operators which can be unary and binary.
The plus sign in python can be used also as right-hand side operator just as minus.
Python Docs:
The unary - (minus) operator yields the negation of its numeric
argument.
The unary + (plus) operator yields its numeric argument unchanged.
