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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 _install_all(destination='', conf_file=''):
 """Use the conf file to list all the third party Odoo add-ons that will be installed and the patches that should be applied. :param string destination: the folder where add-ons should end up at. Default: pwd/3rd :param string conf_file: path to a conf file that describe the add-ons to install. Default: pwd/third_party_addons.yaml """

    dir_path = os.path.dirname(os.path.realpath(__file__))
    destination = destination or os.path.join(dir_path, '..', '3rd')
    conf_file = conf_file or os.path.join(dir_path, '..', "third_party_addons.yaml")
    work_directory = os.path.dirname(os.path.realpath(conf_file))

    with open(conf_file, "r") as conf_data:
        data = yaml.load(conf_data)
        for addons in data:
            _install_one(
                addons['url'],
                addons['branch'],
                os.path.abspath(destination),
                commit=addons.get('commit'),
                patches=addons.get('patches'),
                exclude_modules=addons.get('excludes'),
                include_modules=addons.get('includes'),
                base=addons.get('base'),
                work_directory=work_directory,
            )