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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 style(self, style: _AttrValueType) -> None: """Set style attribute of this node. If argument ``style`` is string, it will be parsed to ``CSSStyleDeclaration``. """

        if isinstance(style, str):
            self.__style._parse_str(style)
        elif style is None:
            self.__style._parse_str('')
        elif isinstance(style, CSSStyleDeclaration):
            self.__style._owner = None
            if style._owner is not None:
                new_style = CSSStyleDeclaration(owner=self)
                new_style.update(style)
                self.__style = new_style
            else:
                # always making new decl may be better
                style._owner = self
                self.__style = style
        else:
            raise TypeError('Invalid type for style: {}'.format(type(style)))