[list] reference and copy (aliasing and clone)

Reference : multiple variables can point same object 

x = [1,2,3,4,5] 
y = x # this is called aliasing

print(y[1]) # 2 

y[1] = 0 
print(y) # [1,0,3,4,5]
print(x) # [1,0,3,4,5]

copy

a = [1,2,3]
b = a[:] # copy or clone 

print(b) # [1,2,3]

a[0] = 10
print(a) # [10,2,3]
print(b) # [1,2,3] modifing a does not affect b

 

Equality and Identity Operators

== checks, if two objects are equal 

is checks, if two objects are the exact same

a = [1,2]
b = a # aliasing
c = a[:] # cloning 

a == b # True
a == c # True

a is b # True
a is c # False