In Linux, using Python 3:

bytes = 32; 
raw_random =  os.getrandom(bytes)
hex_random = hex(
    int.from_bytes(
        raw_random, sys.byteorder
    ))[2:].zfill(2*bytes)
hex_random

Example: 1ded878a7ef3c93389cb08b19a254c846dbd3e88d3b3363dd384977ef81bcc3f

Key is that /dev/urandom is cryptographically secure except just after startup.
The getrandom system call waits until there is enough entropy, compared to reading from /dev/urandom directly.