I notice this in _bootstrap_external.py: the magic number did not get changed, only the comment:


#     Python 3.10a2 3433 (RERAISE restores f_lasti if oparg != 0)
#     Python 3.10a6 3434 (PEP 634: Structural Pattern Matching)
#     Python 3.10a7 3435 Use instruction offsets (as opposed to byte offsets).

#
# MAGIC must change whenever the bytecode emitted by the compiler may no
# longer be understood by older implementations of the eval loop (usually
# due to the addition of new opcodes).
#
# Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
# in PC/launcher.c must also be updated.
MAGIC_NUMBER = (3434).to_bytes(2, 'little') + b'\r\n'
_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c