>>> 5+3
--> 8

>>> 5+'3'
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-152-34a41dff9c04> in <module>()
----> 1 5+'3'

TypeError: unsupported operand type(s) for +: 'int' and 'str'

>>> 5+float('3')
--> 8.0
