import re
payload = b'\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00\x13\x04\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00\x13\x04'
messages = re.split(b'(?:\xff){8}', payload) # Invalid, too many empty elements
print(messages)
messages = re.split(b'(?:(?:\xff){8})+', payload) # Invalid, there are leading empty elements
print(messages)
messages = re.split(b'(?:(?:\xff){8})+', re.sub(b'^(?:(?:\xff){8})+', b'', payload)) # Valid, but not best approach with removing the initial delimiters
print(messages)
messages = [x for x in re.split(b'(?:\xff){8}', payload) if x] # Best approach: let the regex do its work, and discarding emoty elements is left for the if
print(messages)
messages = list(filter(None, messages))
print(messages)

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