[Python] Angle brackets cause re.split() result to become empty string

This example:

import re

regex = r"\[.*?]"
parsed = "start[param1]sep[param2]sep[param3]end"
print(re.split(regex, parsed))
print(re.findall(regex, parsed))


prints the expected result:

['start', 'sep', 'sep', 'end']
['[param1]', '[param2]', '[param3]']


However, as soon as the input string has angle brackets like this:

parsed = "<start>[param1]<sep>[param2]<sep>[param3]<end>"


the output of re.split() becomes empty strings (the re.findall() result obviously remains the same):

['', '', '', '']


I verified that it's because of the angle brackets:

parsed = "start[param1]<sep>[param2]sep[param3]end"


yields

['start', '', 'sep', 'end']


Does anyone know why that happens and if I can suppress this behavior somehow?

In case it's relevant, I'm using Python 3. Not sure if it's specific to Python 3 though. I couldn't find anything about such a behavior anywhere.

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