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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_keyword(self, kwd, *args):
 """Get an item from the fits header, if any."""

        try:
            kwds = self.get_header()
            return kwds[kwd]
        except KeyError:
            # return a default if there is one
            if len(args) > 0:
                return args[0]
            raise KeyError(kwd)