Translation DNA to Protein

Question

I am a biology graduate student and I taught myself a very limited amount of python in the past few months to deal with some data I have. I am not asking for homework help, this

Answer 1

Your problem stems from the line

if cds[n:n+3] in codontable == True

This always evaluates to False, and thus you never append to proteinsequence. Just remove the == True portion like so

if cds[n:n+3] in codontable

and you will get the protein sequence. Also, make sure to return proteinsequence in translate_dna().