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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 find_known_dependencies(self, requirement):
 """ Find the known dependencies of a Python package. :param requirement: A :class:`.Requirement` object. :returns: A list of strings with system package names. """

        logger.info("Checking for known dependencies of %s ..", requirement.name)
        known_dependencies = sorted(self.dependencies.get(requirement.name.lower(), []))
        if known_dependencies:
            logger.info("Found %s: %s", pluralize(len(known_dependencies), "known dependency", "known dependencies"),
                        concatenate(known_dependencies))
        else:
            logger.info("No known dependencies... Maybe you have a suggestion?")
        return known_dependencies