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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 add(self, repo, url):
 """Write custom repository name and url in a file """

        repo_name = []
        if not url.endswith("/"):
            url = url + "/"
        for line in self.custom_repositories_list.splitlines():
            line = line.lstrip()
            if line and not line.startswith("#"):
                repo_name.append(line.split()[0])
        if (repo in self.meta.repositories or repo in repo_name or
                repo in self.meta.default_repositories):
            print("\nRepository name '{0}' exist, select different name.\n"
                  "View all repositories with command 'slpkg "
                  "repo-list'.\n".format(repo))
            raise SystemExit()
        elif len(repo) > 6:
            print("\nslpkg: Error: Maximum repository name length must be "
                  "six (6) characters\n")
            raise SystemExit()
        with open(self.custom_repo_file, "a") as repos:
            new_line = "  {0}{1}{2}\n".format(repo, " " * (10 - len(repo)), url)
            repos.write(new_line)
        repos.close()
        print("\nRepository '{0}' successfully added\n".format(repo))
        raise SystemExit()