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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 _create_default_config(self):
        '''Create and write to disk a default site config file.'''
        # maybe I should read the default config from somewhere in the package?
        cfg = { 'site_title': '',
                'site_subtitle': '',
                'default_author': '',
                'site_url': '',
                'default_theme': 'blog1',
                'default_template': 'main.html.tpl',
                'fixed_frontpage': ''
              }


        file_name = os.path.join(self._dirs['s2'],'config.yml')
        f = open(file_name,'w')
        f.write(yaml.dump(cfg,default_flow_style=False))
        f.close()
        return cfg