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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 css(self) -> str: """Generate a random snippet of CSS. :return: CSS. """

        selector = self.random.choice(CSS_SELECTORS)
        css_sel = '{}{}'.format(selector, self.__text.word())

        cont_tag = self.random.choice(list(HTML_CONTAINER_TAGS.keys()))
        mrk_tag = self.random.choice(HTML_MARKUP_TAGS)

        base = '{}'.format(self.random.choice([cont_tag, mrk_tag, css_sel]))
        props = '; '.join(
            [self.css_property() for _ in range(self.random.randint(1, 6))])
        return '{} {{{}}}'.format(base, props)