str = "4,5cm x55x 22cm ";
str = str.replace('cm', '').replace(' ', '').split('x') # ['4,5', '55', '22']
str = 'cm x '.join(str)+"cm"
print str # retorna 4,5cm x 55cm x 22cm
c3RyID0gIjQsNWNtIHg1NXggMjJjbSAiOwpzdHIgPSBzdHIucmVwbGFjZSgnY20nLCAnJykucmVwbGFjZSgnICcsICcnKS5zcGxpdCgneCcpICMgWyc0LDUnLCAnNTUnLCAnMjInXQpzdHIgPSAnY20geCAnLmpvaW4oc3RyKSsiY20iCnByaW50IHN0ciAjIHJldG9ybmEgNCw1Y20geCA1NWNtIHggMjJjbQo=