Differences between Python 2 and Python 3

division

Python 2 (By default integer division)

assert 1 / 2 == 0

Python 3 (By default true division)

assert 1 / 2 == 0.5

Remedy for Python 2 (forward compatible to Python 3)

from __future__ import division

print

Python 2 (no parentheses)
```
print 'I am a print function'
```
Python 3

print('I am a print function')

Remedy
```
from __future__ import print_function
```

range and xrange

Python 2 (xrange runs identity check)

assert xrange(5) != xrange(5)

Python3 (range runs equality check)

assert range(5) == range(5)

input and raw_input

Python 2 (input() depends on input type)

a = input('a') # ->> 123
print type(a) # <type 'int'>

a = input('a') # ->> '123'
print type(a) # <type 'str'>

Python 2 (raw_input()) and Python 3 (input())
Always return str output.

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