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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 build_static(self, *args, **options):
 """ Builds the static files directory as well as robots.txt and favicon.ico """

        logger.debug("Building static directory")
        if self.verbosity > 1:
            self.stdout.write("Building static directory")
        management.call_command(
            "collectstatic",
            interactive=False,
            verbosity=0
        )

        # Set the target directory inside the filesystem.
        target_dir = path.join(
            self.build_dir,
            settings.STATIC_URL.lstrip('/')
        )
        target_dir = smart_text(target_dir)

        if os.path.exists(self.static_root) and settings.STATIC_URL:
            if getattr(settings, 'BAKERY_GZIP', False):
                self.copytree_and_gzip(self.static_root, target_dir)
            # if gzip isn't enabled, just copy the tree straight over
            else:
                logger.debug("Copying {}{} to {}{}".format("osfs://", self.static_root, self.fs_name, target_dir))
                copy.copy_dir("osfs:///", self.static_root, self.fs, target_dir)

        # If they exist in the static directory, copy the robots.txt
        # and favicon.ico files down to the root so they will work
        # on the live website.
        robots_src = path.join(target_dir, 'robots.txt')
        if self.fs.exists(robots_src):
            robots_target = path.join(self.build_dir, 'robots.txt')
            logger.debug("Copying {}{} to {}{}".format(self.fs_name, robots_src, self.fs_name, robots_target))
            self.fs.copy(robots_src, robots_target)

        favicon_src = path.join(target_dir, 'favicon.ico')
        if self.fs.exists(favicon_src):
            favicon_target = path.join(self.build_dir, 'favicon.ico')
            logger.debug("Copying {}{} to {}{}".format(self.fs_name, favicon_src, self.fs_name, favicon_target))
            self.fs.copy(favicon_src, favicon_target)