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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 delete_policy(vhost, name, runas=None):
    '''
    Delete a policy based on rabbitmqctl clear_policy.

    Reference: http://www.rabbitmq.com/ha.html

    CLI Example:

    .. code-block:: bash

        salt '*' rabbitmq.delete_policy / HA
    '''
    if runas is None and not salt.utils.platform.is_windows():
        runas = salt.utils.user.get_user()
    res = __salt__['cmd.run_all'](
        [RABBITMQCTL, 'clear_policy', '-p', vhost, name],
        reset_system_locale=False,
        runas=runas,
        python_shell=False)
    log.debug('Delete policy: %s', res['stdout'])
    return _format_response(res, 'Deleted')