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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_kwarg_names(func):
 """ Return a list of valid kwargs to function func """

    sig = inspect.signature(func)
    kwonlyargs = [p.name for p in sig.parameters.values()
                  if p.default is not p.empty]
    return kwonlyargs