remove last 76 letters from string

[MRAB]

Iain King wrote:
>>      print >>nucleotides, seq[-76]
> 
>>      last_part = line.rstrip()[-76 : ]
> 
> You all mean:   seq[:-76]   , right? (assuming you've already stripped
> any junk off the end of the string)
> 
The OP said "cut out the last 76 letters (nucleotides) from each
individual sequence and send them to a new txt file with a similar 
format.", ie extract the last 76 letters (in the same format) to a file.