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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_required_args(fn) -> list: """ Returns a list of required arguments for the function fn. ['x', 'y'] ['x'] """

    sig = inspect.signature(fn)
    return [
        name for name, param in sig.parameters.items()
        if param.default == inspect._empty and param.kind not in VAR_ARGS
    ]