help please

[Steven Bethard]

gargonx wrote:
> yes the items in std are always single to single, and ext single to
> double. basicly the ext are refernce to the std itmes. the second
> character in ext is a number depending on how far it is from the item
> in std. this is just a simple encoding program.

If your keys are always single characters (as this description seems to 
suggest) then the last code I posted should do what you want.  Repeated 
here for your enjoyment:

# merge mappings:
# std has highest precedence, then ext, then punc
replacements = {}
replacements.update(punc)
replacements.update(ext)
replacements.update(std)

# define encoding procedure
def proc(text):
     # replace each character with its replacement
     # or leave character unchanged if not in the mapping
     return ''.join([replacements.get(c, c) for c in text])

Steve