What does -> mean in Python function definitions?

Question

I\'ve recently noticed something interesting when looking at Python 3.3 grammar specification:

funcdef: \'def\' NAME parameters [\'->\' test] \':\' suite
         


        

Answer 1

def f(x) -> str:
return x+4

print(f(45))

# will give the result : 
49

# or with other words '-> str' has NO effect to return type:

print(f(45).__class__)