I am trying to solve the already asked question link with one liner. But not getting expected.
d={'Old': 'New', 'old': 'new'}
strr='Old, not old'
Attempt
[ strr.replace(k,v) for k,v in d.items() if k in strr]
Out[19]: ['New, not old', 'Old, not new']
Expected
New, not new