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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 consume(self, source):
 """ Parse source and consume tokens from tinycss2. Arguments: source (string):
 Source content to parse. Returns: dict: Retrieved rules. """

        manifest = OrderedDict()

        rules = parse_stylesheet(
            source,
            skip_comments=True,
            skip_whitespace=True,
        )

        for rule in rules:
            # Gather rule selector+properties
            name = self.digest_prelude(rule)

            # Ignore everything out of styleguide namespace
            if not name.startswith(RULE_BASE_PREFIX):
                continue

            properties = self.digest_content(rule)
            manifest[name] = properties

        return manifest