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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 _legacy_bpf_pointer(tcpdump_lines):
 """Get old-format BPF Pointer. Deprecated"""

    X86_64 = os.uname()[4] in ['x86_64', 'aarch64']
    size = int(tcpdump_lines[0])
    bpf = b""
    for l in tcpdump_lines[1:]:
        if six.PY2:
            int_type = long  # noqa: F821
        else:
            int_type = int
        bpf += struct.pack("HBBI", *map(int_type, l.split()))

    # Thanks to http://www.netprojects.de/scapy-with-pypy-solved/ for the pypy trick  # noqa: E501
    if conf.use_pypy:
        str_buffer = ctypes.create_string_buffer(bpf)
        return struct.pack('HL', size, ctypes.addressof(str_buffer))
    else:
        # XXX. Argl! We need to give the kernel a pointer on the BPF,
        # Python object header seems to be 20 bytes. 36 bytes for x86 64bits arch.  # noqa: E501
        if X86_64:
            return struct.pack("HL", size, id(bpf) + 36)
        else:
            return struct.pack("HI", size, id(bpf) + 20)