Here are a few question-based titles that capture the essence of the provided article: * Chained Assignments in Python: Why Does `x = y = somefunction()` Work Like This? * How Does Python Handle Chai

Chained Assignments and Order of Evaluation

Chained assignments, such as x = y = somefunction(), can be confusing due to their departure from the expected order of evaluation. Contrary to the assumption that x = somefunction() and y = somefunction() are executed in sequence, chained assignments follow a different pattern.

Left-to-Right Assignment

In a chained assignment, the leftmost target variable is assigned first. This means that the following code:

<code class="python">x = y = somefunction()</code>

is equivalent to:

<code class="python">temp = somefunction()
x = temp
y = temp</code>

As you can see, the value returned by somefunction() is first stored in a temporary variable (temp) and then assigned to both x and y.

Caution with Mutable Objects

It's crucial to note that in chained assignments, the same object is always assigned to each target. This can lead to unintended consequences when dealing with mutable objects like lists. For example, the following code:

<code class="python">x = y = []</code>

assigns the same list object to both x and y. This means that any modifications made to x will also be reflected in y.

To avoid this issue, always create distinct objects for mutable variables, as seen in the following correct example:

<code class="python">x = []
y = []</code>

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