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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 enable(self, force=False):
 """ Enable this site """

        log = logging.getLogger('ipsv.models.sites.site')
        log.debug('Disabling all other sites under the domain %s', self.domain.name)
        Session.query(Site).filter(Site.id != self.id).filter(Site.domain == self.domain).update({'enabled': 0})

        sites_enabled_path = _cfg.get('Paths', 'NginxSitesEnabled')
        server_config_path = os.path.join(_cfg.get('Paths', 'NginxSitesAvailable'), self.domain.name)
        server_config_path = os.path.join(server_config_path, '{fn}.conf'.format(fn=self.slug))
        symlink_path = os.path.join(sites_enabled_path, '{domain}-{fn}'.format(domain=self.domain.name,
                                                                               fn=os.path.basename(server_config_path)))
        links = glob(os.path.join(sites_enabled_path, '{domain}-*'.format(domain=self.domain.name)))
        for link in links:
            if os.path.islink(link):
                log.debug('Removing existing configuration symlink: %s', link)
                os.unlink(link)
            else:
                if not force:
                    log.error('Configuration symlink path already exists, but it is not a symlink')
                    raise Exception('Misconfiguration detected: symlink path already exists, but it is not a symlink '
                                    'and --force was not passed. Unable to continue')
                log.warn('Configuration symlink path already exists, but it is not a symlink. Removing anyways '
                         'since --force was set')
                if os.path.isdir(symlink_path):
                    shutil.rmtree(symlink_path)
                else:
                    os.remove(symlink_path)

        log.info('Enabling Nginx configuration file')
        os.symlink(server_config_path, symlink_path)

        self.enabled = 1
        Session.commit()