[BioPython] back translation

[Edoardo Saccenti]

Hi Folks,
I'm wondering if there is a way using biopython to get ALL the possible
back translation of a given protein sequence.

Following the example on the cookbook I only get one DNA sequence!

I googled and I found this:
"""""
To get a list of all posible codons, replace
  for key in keys:
      back_table[table[key]] = key
with
  for key in keys:
      back_table[table[key]] = back_table.get(table[key], []) +
                               [key]
""""

I tried to modify but, of course, I get an error from the string package

Does anybod had to deal with this problem before?

Ciao
Edoardo