Python id () function decryption process-Python tutorial

The id () function is frequently used. For this reason, I will study this function in depth and share the code with you, hoping to help you >>> a = 2.5
>>> B = 2.5
>>> C = B
>>> A is c
False

>>> A = 2
>>> B = 2
>>> C = B
>>> A is c
True

When I use the is function today, I print the numbers a and B are assigned 2.5 and 2 respectively. I found that:
>>> A = 2
>>> B = 2
>>> Id ()
21132060
>>> Id (B)
21132060
>>> A = 2.5
>>> B = 2.5
>>> Id ()
19622112
>>> Id (B)
29321464

When a and B are 2, the id is the same, but 2.5 is different. this problem also occurs when the string is short, when B is assigned a very short string, their IDs are the same, but long strings do not;
Then, we can get a simple conclusion: the interpreter makes a small optimization for int and short strings with a small value, and only allocates one object, let them have the same id.