Understanding the Python.org help files [duplicate] - python

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What is the meaning of a forward slash "/" in a Python method signature, as shown by help(foo)? [duplicate]
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Pythonestas,
I can't find any guidance or explanation of the Python help documentation?
As an example, what does the "*" and the "/" refer to?
If the default value for key = None, where are the explanations for what can be used for the key argument?
sorted(iterable, /, *, key=None, reverse=False)ΒΆ
Thanks in advance!
Cannot find the answer in the Python.org docs.

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