Identity vs. equality
Last Updated: February 3, 2018 12:20 PM UTC
Last edited by:
Joseph <joseph@josephbanks.me>
Initial Commit
THIS IS FAKE DEMO DATA

Should I be using is or ==?

To check if two objects are equal, use the equality operator (==). 

x = 5
if x == 5:
    print("x equals 5")
if x == 3:
    print("x equals 3")
# Prints 'x equals 5'
To check if two objects are actually the same thing in memory, use the identity comparison operator (is). 
>>> list_1 = [1, 2, 3]
>>> list_2 = [1, 2, 3]
>>> if list_1 is [1, 2, 3]:
...    print("list_1 is list_2")
...
>>> reference_to_list_1 = list_1
>>> if list_1 is reference_to_list_1:
...    print("list_1 is reference_to_list_1")
...
list_1 is reference_to_list_1