Python: what difference between 'is' and '=='?
python
Solution
`is` checks for identity. `a is b` is `True` iff `a` and `b` are the same object (they are both stored in the same memory address).
`==` checks for equality, which is usually defined by the magic method `__eq__` - i.e., `a == b` is `True` if `a.__eq__(b)` is `True`.
In your case specifically, Python optimizes the two hardcoded strings into the same object (since strings are immutable, there's no danger in that). Since `input()` will create a string at runtime, it can't do that optimization, so a new string object is created.
Problem
I'm trying next code: ``` x = 'asd' y = 'asd' z = input() #write here string 'asd'. For Python 2.x use raw_input() x == y # True. x is y # True. x == z # True. x is z # False. ``` Why we have false in last expression?