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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_convert(hdr):
 """Convert a Netlink message received from a Netlink socket to an nl_msg. https://github.com/thom311/libnl/blob/libnl3_2_25/lib/msg.c#L382 Allocates a new Netlink message and copies all of the data in `hdr` into the new message object. Positional arguments: hdr -- Netlink message received from netlink socket (nlmsghdr class instance). Returns: Newly allocated Netlink message (nl_msg class instance) or None. """

    nm = nlmsg_alloc(hdr.nlmsg_len)
    if not nm:
        return None
    nm.nm_nlh.bytearray = hdr.bytearray.copy()[:hdr.nlmsg_len]
    return nm