How to map a read-only buffer to ctypes.Structure?

Question

Python

python3.3, win32
has a chunk of memory available for reading

m = mmap.mmap(0, MEMMAPFILESIZE, MEMMAPFILE, access=mmap.ACCESS_READ)

from it I want to get an object with fields for reading from this memory directly, but I don’t want to create a class with a bunch of properties and manual reading at the right offsets
, now I did this

header_struct = struct.Struct('i')
Header = collections.namedtuple('Header', 'version')
h = Header._make(header_struct.unpack_from(m))
print(h.version)

the problem is that the values ​​in memory are dynamic, another program changes them, and this method only copies the memory, besides, auto-completion will not work
if done through Structure

class Header(ctypes.Structure):
    _fields_ = [
        ('version', ctypes.c_int),
    ]
h = Header.from_buffer(m)

this causes an error, since the buffer must be writable,
but I want it to be beautiful and simple