Replace pg_ident.conf content in the PGDATA if ident_file is not defined in the
        `postgresql.parameters` and pg_ident is defined in the `postgresql` section.

        :returns: True if pg_ident.conf was rewritten.

def _replace_pg_ident(self):
        """
        Replace pg_ident.conf content in the PGDATA if ident_file is not defined in the
        `postgresql.parameters` and pg_ident is defined in the `postgresql` section.

        :returns: True if pg_ident.conf was rewritten.
        """

        if not self._server_parameters.get('ident_file') and self.config.get('pg_ident'):
            with open(self._pg_ident_conf, 'w') as f:
                f.write(self._CONFIG_WARNING_HEADER)
                for line in self.config['pg_ident']:
                    f.write('{0}\n'.format(line))
            return True