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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 init(cls, path=None, mkdir=True, odbt=GitCmdObjectDB, expand_vars=True, **kwargs):
 """Initialize a git repository at the given path if specified :param path: is the full path to the repo (traditionally ends with /<name>.git) or None in which case the repository will be created in the current working directory :param mkdir: if specified will create the repository directory if it doesn't already exists. Creates the directory with a mode=0755. Only effective if a path is explicitly given :param odbt: Object DataBase type - a type which is constructed by providing the directory containing the database objects, i.e. .git/objects. It will be used to access all object data :param expand_vars: if specified, environment variables will not be escaped. This can lead to information disclosure, allowing attackers to access the contents of environment variables :param kwargs: keyword arguments serving as additional options to the git-init command :return: ``git.Repo`` (the newly created repo)"""

        if path:
            path = expand_path(path, expand_vars)
        if mkdir and path and not osp.exists(path):
            os.makedirs(path, 0o755)

        # git command automatically chdir into the directory
        git = Git(path)
        git.init(**kwargs)
        return cls(path, odbt=odbt)