as1.py

x=5
y=x
#Both x and y are pointing to same int object.
print (id(x))#Output:1547167728
print (id(y))#Output:1547167728

#Modifying value of 'y'
y=10
print (y)
#After modifying 'y' will point to other 'int' object.
print (id(y))#Output:1547167808

#'x' value is not changed.
print (x)#Output:5
print (id(x))#Output:1547167728
print (id(y))#Output:1547167808