def decodeer(bericht):
"""
>>> decodeer('Oea ie.mtat n')
'One at a time.'
>>> decodeer("W'entwies u o,cnw ev.erse a ybtb,rta o re")
"We're not waiters, but boy, can we serve."
>>> decodeer('Dtn enspae srsy oemasntigt s.uo nho ne vL.ki iryl intagia')
'Dating a tennis player is risky. Love means nothing to us.'
"""
def codeer(bericht):
"""
>>> codeer('One at a time.')
'Oea ie.mtat n'
>>> codeer("We're not waiters, but boy, can we serve.")
"W'entwies u o,cnw ev.erse a ybtb,rta o re"
>>> codeer('Dating a tennis player is risky. Love means nothing to us.')
'Dtn enspae srsy oemasntigt s.uo nho ne vL.ki iryl intagia'
"""
if __name__ == '__main__':
import doctest
doctest.testmod()