Why this program giving answer false? explain it

Question

a=[123] b=a[:] b is a this program giving me the answer false. why the answer is false. explain it please.thanks in advance.

Rajkiran Swain · Answer

Please accept this answer if you like this.

Rajkiran Swain · Answer

The reason why this program is giving the answer false is because the is keyword in Python checks for object identity which means it checks whether the two variables refer to the same object in memory. In this case although the contents of the a and b lists are the same they are two distinct objects with different memory locations. When you create a slice of a list in Python (in this case b=a[:]) it creates a new object with the same contents as the original list but a different memory location. So a and b may have the same values but they are not the same object. To illustrate this you can use the id() function in Python to check the memory location of each object: a = [1 2 3] b = a[:] print(id(a)) # Output: 140215013479232 print(id(b)) # Output: 140215013735168 print(b is a) # Output: False As you can see the memory locations of a and b are different which means they are not the same object. However if you compare the values of a and b they are the same: print(a == b) # Output: True So if you want to check whether two lists have the same values you should use the == operator rather than the is operator.

MD NAYEEM · Answer

Thanks mate for your excellent explanation.