difference between next() and .__next__

[akbarza]

Hi
in the below code:

def g():
    for i in range(3):
        yield i*i
my_g=g()
my_g.__next__()
next(my_g)
#what is difference between .__next__() and next() ?

next() and .__next__() will show next elements to us. what is the difference between them?
Is the usage of them different?
thanks