Is it safe to rely on Python function arguments evaluation order? [duplicate]

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Quoting from the reference documentation:

Python evaluates expressions from left to right.

So yes, you can count on that (with one exception, see below).

A call (the (...) part after a primary, such as a function name) is just another expression primary, and the arguments for the call are just more expressions.

Note: There is one exception to this rule. When using *expression in a call (to expand an iterable to form additional positional arguments), then this expression is evaluated before any keyword argument expressions:

>>> from itertools import count
>>> def bar(n, r=(), c=count()): print(f'{next(c)}: bar({n!r})'); return r
...
>>> def foo(*args, **kwargs): pass
...
>>> foo(bar('a1'), spam=bar('a2'), *bar('varargs'), **bar('kwargs', {}))
0: bar('a1')
1: bar('varargs')
2: bar('a2')
3: bar('kwargs')

The linked documentation states:

A consequence of this is that although the *expression syntax may appear after explicit keyword arguments, it is processed before the keyword arguments[.]

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