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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_backup(name):
    r'''
    Backup an IIS Configuration on the System.

    .. versionadded:: 2017.7.0

    .. note::
        Backups are stored in the ``$env:Windir\System32\inetsrv\backup``
        folder.

    Args:
        name (str): The name to give the backup

    Returns:
        bool: True if successful, otherwise False

    CLI Example:

    .. code-block:: bash

        salt '*' win_iis.create_backup good_config_20170209
    '''
    if name in list_backups():
        raise CommandExecutionError('Backup already present: {0}'.format(name))

    ps_cmd = ['Backup-WebConfiguration',
              '-Name', "'{0}'".format(name)]

    cmd_ret = _srvmgr(ps_cmd)

    if cmd_ret['retcode'] != 0:
        msg = 'Unable to backup web configuration: {0}\nError: {1}' \
              ''.format(name, cmd_ret['stderr'])
        raise CommandExecutionError(msg)

    return name in list_backups()