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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 parse(self, src):
 """Parses CSS string source using the current cssBuilder. Use for embedded stylesheets."""


        self.cssBuilder.beginStylesheet()
        try:

            # XXX Some simple preprocessing
            src = cssSpecial.cleanupCSS(src)

            try:
                src, stylesheet = self._parseStylesheet(src)
            except self.ParseError as err:
                err.setFullCSSSource(src)
                raise
        finally:
            self.cssBuilder.endStylesheet()
        return stylesheet