How to use the certbot.compat.os.path function in certbot

def _account_dir_path_for_server_path(self, account_id, server_path):
        accounts_dir = self.config.accounts_dir_for_server_path(server_path)
        return os.path.join(accounts_dir, account_id)

def validate_file(filename):
    """Ensure that the specified file exists."""

    if not os.path.exists(filename):
        raise errors.PluginError('File not found: {0}'.format(filename))

    if os.path.isdir(filename):
        raise errors.PluginError('Path is a directory: {0}'.format(filename))

:param str path: Certificate save directory.

    :returns: CSR
    :rtype: :class:`certbot.util.CSR`

    """
    config = zope.component.getUtility(interfaces.IConfig)

    csr_pem = acme_crypto_util.make_csr(
        privkey.pem, names, must_staple=config.must_staple)

    # Save CSR
    util.make_or_verify_dir(path, 0o755, config.strict_permissions)
    csr_f, csr_filename = util.unique_file(
        os.path.join(path, "csr-certbot.pem"), 0o644, "wb")
    with csr_f:
        csr_f.write(csr_pem)
    logger.debug("Creating CSR: %s", csr_filename)

    return util.CSR(csr_filename, csr_pem, "pem")

def lock_dir(dir_path):
    # type: (str) -> LockFile
    """Place a lock file on the directory at dir_path.

    The lock file is placed in the root of dir_path with the name
    .certbot.lock.

    :param str dir_path: path to directory

    :returns: the locked LockFile object
    :rtype: LockFile

    :raises errors.LockError: if unable to acquire the lock

    """
    return LockFile(os.path.join(dir_path, '.certbot.lock'))

:param str cert_pem:
        :param str chain_pem:
        :param str cert_path: Candidate path to a certificate.
        :param str chain_path: Candidate path to a certificate chain.
        :param str fullchain_path: Candidate path to a full cert chain.

        :returns: cert_path, chain_path, and fullchain_path as absolute
            paths to the actual files
        :rtype: `tuple` of `str`

        :raises IOError: If unable to find room to write the cert files

        """
        for path in cert_path, chain_path, fullchain_path:
            util.make_or_verify_dir(os.path.dirname(path), 0o755, self.config.strict_permissions)


        cert_file, abs_cert_path = _open_pem_file('cert_path', cert_path)

        try:
            cert_file.write(cert_pem)
        finally:
            cert_file.close()
        logger.info("Server issued certificate; certificate written to %s",
                    abs_cert_path)

        chain_file, abs_chain_path =\
                _open_pem_file('chain_path', chain_path)
        fullchain_file, abs_fullchain_path =\
                _open_pem_file('fullchain_path', fullchain_path)

def _find_config_root(self):
        """Return the Nginx Configuration Root file."""
        location = ['nginx.conf']

        for name in location:
            if os.path.isfile(os.path.join(self.root, name)):
                return os.path.join(self.root, name)

        raise errors.NoInstallationError(
            "Could not find Nginx root configuration file (nginx.conf)")

def save(self, title=None, temporary=False):
        """Creates backups and writes changes to configuration files.

        :param str title: The title of the save. If a title is given, the
            configuration will be saved as a new checkpoint and put in a
            timestamped directory. `title` has no effect if temporary is true.

        :param bool temporary: Indicates whether the changes made will
            be quickly reversed in the future (challenges)

        :raises errors.PluginError: when save is unsuccessful
        """
        save_files = set((os.path.join(self.conf('config-dir'), "main.cf"),))
        self.add_to_checkpoint(save_files,
                               "\n".join(self.save_notes), temporary)
        self.postconf.flush()

        del self.save_notes[:]

        if title and not temporary:
            self.finalize_checkpoint(title)

import shlex

import mock


# http://docs.readthedocs.org/en/latest/faq.html#i-get-import-errors-on-libraries-that-depend-on-c-modules
# c.f. #262
sys.modules.update(
    (mod_name, mock.MagicMock()) for mod_name in ['augeas'])

here = os.path.abspath(os.path.dirname(__file__))

# If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here.
sys.path.insert(0, os.path.abspath(os.path.join(here, '..')))

# -- General configuration ------------------------------------------------

# If your documentation needs a minimal Sphinx version, state it here.
needs_sphinx = '1.0'

# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
# ones.
extensions = [
    'sphinx.ext.autodoc',
    'sphinx.ext.intersphinx',
    'sphinx.ext.todo',
    'sphinx.ext.coverage',
    'sphinx.ext.viewcode',
]

def revert_temporary_config(self):
        """Reload users original configuration files after a temporary save.

        This function should reinstall the users original configuration files
        for all saves with temporary=True

        :raises .ReverterError: when unable to revert config

        """
        if os.path.isdir(self.config.temp_checkpoint_dir):
            try:
                self._recover_checkpoint(self.config.temp_checkpoint_dir)
            except errors.ReverterError:
                # We have a partial or incomplete recovery
                logger.critical(
                    "Incomplete or failed recovery for %s",
                    self.config.temp_checkpoint_dir,
                )
                raise errors.ReverterError("Unable to revert temporary config")