<b> followed by <b> before closing</b>

[Axel_Erfurt]

something like that

import re

s = "<RF><b>1:4 <b>Hom wat is ... kom:</b>"

def repl(match, count=[0]):
    x, = count
    count[0] += 1
    if x > 0:
        return ''
    return '<b>'


print(re.sub('<b>', repl, s))

Output:
<RF><b>1:4 Hom wat is ... kom:</b>