How to write list of integers to file with struct.pack_into?

[MRAB]

On 2023-10-01 23:04, Jen Kris via Python-list wrote:
 >
 > Iwant to write a list of 64-bit integers to a binary file. 
Everyexample I have seen in my research convertsit to .txt, but I want 
it in binary.  I wrote this code,based on some earlier work I have done:
 >
 > buf= bytes((len(qs_array)) * 8)
 >
 > foroffset in range(len(qs_array)):
 >
 > item_to_write= bytes(qs_array[offset])
 >
 > struct.pack_into(buf,"<Q", offset, item_to_write)
 >
 > ButI get the error "struct.error: embedded null character."
 >
 > Maybethere's a better way to do this?
 >
You can't pack into a 'bytes' object because it's immutable.

The simplest solution I can think of is:

buf = struct.pack("<%sQ" % len(qs_array), *qs_array)