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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_server(name, backend, socket=DEFAULT_SOCKET_URL):
    '''
    Enable Server in haproxy

    name
        Server to enable

    backend
        haproxy backend, or all backends if "*" is supplied

    socket
        haproxy stats socket, default ``/var/run/haproxy.sock``

    CLI Example:

    .. code-block:: bash

        salt '*' haproxy.enable_server web1.example.com www
    '''

    if backend == '*':
        backends = show_backends(socket=socket).split('\n')
    else:
        backends = [backend]

    results = {}
    for backend in backends:
        ha_conn = _get_conn(socket)
        ha_cmd = haproxy.cmds.enableServer(server=name, backend=backend)
        ha_conn.sendCmd(ha_cmd)
        results[backend] = list_servers(backend, socket=socket)

    return results