Problem scenario
You are running a Python script. You keep getting “SyntaxError: invalid syntax” and a line number. You can find nothing wrong with the syntax on the specified line number. What do you do?

Possible solution #1
Look at the line with code, as opposed to blank line(s), above it. Is there a missing quote, brace, bracket or parentheses?

Possible solution #2
Are you trying to use an “if” statement on one line?

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Problem scenario
You have a list in Python that you copy into another variable. You change the original list and the copied version changes. Why does the copied version get copied and what can you do to overcome this?

Solution
There is something called a “deep” copy and a “shallow” copy. This program will illustrate both the problem and the solution:

list_a = [3, …

Continue reading “Why in Python Does a Variable Copy Get Changed when You Change Its Source?”

Problem scenario
You want to use the copy feature in Python. What do you do?

Solution
To see the different types of copying, use a mutable object such as a list. Here is an example:

import copy

var1 = [1, 2, 3, 4]
shallow_copy = var1
deep_copy = copy.deepcopy(var1)
var1.append(999999999999)

print()
print(shallow_copy)
print(” — Shallow copy above and deep copy below —.”)
print(deep_copy)

For most (or perhaps all) intents and purposes,

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