September 2026
1051 pages
35h 4m
English
Content preview from Python 3 - Second Edition
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7.2 Deleting References
During a program run, usually a lot of instances are created, but not all of them are needed all the time. Let’s consider the following fictitious program start:
welcome = "Welcome to the sample program"print(welcome)# From this point on the rest of the program would continue
It’s easy to see that the instance referenced by welcome is no longer needed after the welcome and thus wastes memory without any purpose during the rest of the program runtime. What’s preferable here is a way to remove instances on request that are no longer needed.
Python doesn’t allow programmers to manage the memory directly; it instead does that for them. As a result, we can’t manually delete existing instances but must rely on an automatism ...
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