[BioPython] Cookbook:RenameFasta

[Mike Dyall-Smith]

Njm revised the code of Humberto at:
http://bio.scipy.org/wiki/index.php/RenameFastaSequences
to make it more idiomatic Python. I altered my discussion according
to the new code. However, when I tested it on a fasta file I get an  
error:

   File "REnameFasta2.py", line 6, in <module>
     filename, basename = sys.argv
ValueError: too many values to unpack

If I revert back to the old code for this line, ie. replace
   ' filename, basename = sys.argv'
with
    'filename = sys.argv[1] '
    'basename = sys.argv[2]'

it works fine.  I assume there is some subtle error in assigning two
names to sys.argv

Regards, Mike D-S