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pythondefault-valuekeyword-argument

Proper way to use **kwargs in Python

What is the proper way to use **kwargs in Python when it comes to default values?

kwargs returns a dictionary, but what is the best way to set default values, or is there one? Should I just access it as a dictionary? Use get function?

class ExampleClass:
    def __init__(self, **kwargs):
        self.val = kwargs['val']
        self.val2 = kwargs.get('val2')

People do it different ways in code that I've seen and it's hard to know what to use.

Solution

  • You can pass a default value to get() for keys that are not in the dictionary:

    self.val2 = kwargs.get('val2',"default value")

    However, if you plan on using a particular argument with a particular default value, why not use named arguments in the first place?

    def __init__(self, val2="default value", **kwargs):