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