What are type hints in Python 3.5?

Question

One of the most talked about features in Python 3.5 is type hints.

An example of type hints is mentioned in this article and this o

Answer 1

Type-hints are for maintainability and don't get interpreted by Python. In the code below, the line def add(self, ic:int) doesn't result in an error until the next return... line:

class C1:
    def __init__(self):
        self.idn = 1
    def add(self, ic: int):
        return self.idn + ic
    
c1 = C1()
c1.add(2)

c1.add(c1)
Traceback (most recent call last):
  File "", line 1, in 
  File "", line 5, in add
TypeError: unsupported operand type(s) for +: 'int' and 'C1'