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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 nlmsg_alloc(len_=default_msg_size):
 """Allocate a new Netlink message with maximum payload size specified. https://github.com/thom311/libnl/blob/libnl3_2_25/lib/msg.c#L299 Allocates a new Netlink message without any further payload. The maximum payload size defaults to resource.getpagesize() or as otherwise specified with nlmsg_set_default_size(). Returns: Newly allocated Netlink message (nl_msg class instance). """

    len_ = max(libnl.linux_private.netlink.nlmsghdr.SIZEOF, len_)
    nm = nl_msg()
    nm.nm_refcnt = 1
    nm.nm_nlh = libnl.linux_private.netlink.nlmsghdr(bytearray(b'\0') * len_)
    nm.nm_protocol = -1
    nm.nm_size = len_
    nm.nm_nlh.nlmsg_len = nlmsg_total_size(0)
    _LOGGER.debug('msg 0x%x: Allocated new message, maxlen=%d', id(nm), len_)
    return nm