Python `__mod__`: Modulo for numbers, interpolation for str

The % in Python, on numbers, is modulo:

x = 10
y = 3
x % y          # 1
x.__mod__(y)   # same thing, 1

But str uses __mod__ for interpolation:

s = 'Hi, %d'
s % y        # 'Hi, 3'
s.__mod__(y) # Same thing, 'Hi, 3'

Same operator, same magic method — but totally different.