I want to create a program that translates DNA sequences into amino acid sequences. So I used Biopython. here's what i have so far

import sys
from Bio import SeqIO
import warnings
warnings.filterwarnings("ignore")
filename = raw_input("Enter filename : ")
myfile = open(filename)
fasta_in=filename

for record in SeqIO.parse(fasta_in,'fasta'):
     id_part=record.id
     desc_part=record.description
     seq = record.seq

     print('seq:',seq)

print(seq);
frame_num = raw_input("Enter frame number: ")
if (frame_num[0] == '+'):
   for codon in [seq[i:i+3] for i in range(int(frame_num[1])-1, len(seq), 3)]:
      print seq.translate()
      sys.exit()



else:
for codon in [seq[i-3:i] for i in range(len(seq)-int(frame_num[1])+1, 0, -3)]:
    print seq.translate()
    sys.exit

I ran this program, but the same amino acid sequence translation was printed at +1 and -2. Like this:

Enter filename : ringo.txt
('seq:', Seq('TTCAGGAGTGGAACGCACGCCAGCGACGTCCAAGAAGCCTTGAAACAGTTCGTC...TTT', SingleLetterAlphabet()))
('seq:', Seq('ATGGGAAGAAGGCGAAGTCATGAGCGCCGGGATTTACCCCCTAACCTTTATATA...TAA', SingleLetterAlphabet()))ATGGGAAGAAGGCGAAGTCATGAGCGCCGGGATTTACCCCCTAACCTTTATATAAGAAACAATGGATATTACTGCTACAGGGACCCAAGGACGGGTAAAGAGTTTGGATTAGGCAGAGACAGGCGAATCGCAATCACTGAAGCTATACAGGCCAACATTGAGTTATTTTCAGGACACAAACACAAGCCTCTGACAGCGAGAATCAACAGTGATAATTCCGTTACGTTACATTCATGGCTTGATCGCTACGAAAAAATCCTGGCCAGCAGAGGAATCAAGCAGAAGACACTCATAAATTACATGAGCAAAATTAAAGCAATAAGGAGGGGTCTGCCTGATGCTCCACTTGAAGACATCACCACAAAAGAAATTGCGGCAATGCTCAATGGATACATAGACGAGGGCAAGGCGGCGTCAGCCAAGTTAATCAGATCAACACTGAGCGATGCATTCCGAGAGGCAATAGCTGAAGGCCATATAACAACAAACCATGTCGCTGCCACTCGCGCAGCAAAATCAGAGGTAAGGAGATCAAGACTTACGGCTGACGAATACCTGAAAATTTATCAAGCAGCAGAATCATCACCATGTTGGCTCAGACTTGCAATGGAACTGGCTGTTGTTACCGGGCAACGAGTTGGTGATTTATGCGAAATGAAGTGGTCTGATATCGTAGATGGATATCTTTATGTCGAGCAAAGCAAAACAGGCGTAAAAATTGCCATCCCAACAGCATTGCATATTGATGCTCTCGGAATATCAATGAAGGAAACACTTGATAAATGCAAAGAGATTCTTGGCGGAGAAACCATAATTGCATCTACTCGTCGCGAACCGCTTTCATCCGGCACAGTATCAAGGTATTTTATGCGCGCACGAAAAGCATCAGGTCTTTCCTTCGAAGGGGATCCGCCTACCTTTCACGAGTTGCGCAGTTTGTCTGCAAGACTCTATGAGAAGCAGATAAGCGATAAGTTTGCTCAACATCTTCTCGGGCATAAGTCGGACACCATGGCATCACAGTATCGTGATGACAGAGGCAGGGAGTGGGACAAAATTGAAATCAAATAA
Enter frame number: +1


MGRRRSHERRDLPPNLYIRNNGYYCYRDPRTGKEFGLGRDRRIAITEAIQANIELFSGHKHKPLTARINSDNSVTLHSWLDRYEKILASRGIKQKTLINYMSKIKAIRRGLPDAPLEDITTKEIAAMLNGYIDEGKAASAKLIRSTLSDAFREAIAEGHITTNHVAATRAAKSEVRRSRLTADEYLKIYQAAESSPCWLRLAMELAVVTGQRVGDLCEMKWSDIVDGYLYVEQSKTGVKIAIPTALHIDALGISMKETLDKCKEILGGETIIASTRREPLSSGTVSRYFMRARKASGLSFEGDPPTFHELRSLSARLYEKQISDKFAQHLLGHKSDTMASQYRDDRGREWDKIEIK*

And '-2'

Enter filename : ringo.txt
('seq:', Seq('TTCAGGAGTGGAACGCACGCCAGCGACGTCCAAGAAGCCTTGAAACAGTTCGTC...TTT', SingleLetterAlphabet()))
('seq:', Seq('ATGGGAAGAAGGCGAAGTCATGAGCGCCGGGATTTACCCCCTAACCTTTATATA...TAA', SingleLetterAlphabet()))ATGGGAAGAAGGCGAAGTCATGAGCGCCGGGATTTACCCCCTAACCTTTATATAAGAAACAATGGATATTACTGCTACAGGGACCCAAGGACGGGTAAAGAGTTTGGATTAGGCAGAGACAGGCGAATCGCAATCACTGAAGCTATACAGGCCAACATTGAGTTATTTTCAGGACACAAACACAAGCCTCTGACAGCGAGAATCAACAGTGATAATTCCGTTACGTTACATTCATGGCTTGATCGCTACGAAAAAATCCTGGCCAGCAGAGGAATCAAGCAGAAGACACTCATAAATTACATGAGCAAAATTAAAGCAATAAGGAGGGGTCTGCCTGATGCTCCACTTGAAGACATCACCACAAAAGAAATTGCGGCAATGCTCAATGGATACATAGACGAGGGCAAGGCGGCGTCAGCCAAGTTAATCAGATCAACACTGAGCGATGCATTCCGAGAGGCAATAGCTGAAGGCCATATAACAACAAACCATGTCGCTGCCACTCGCGCAGCAAAATCAGAGGTAAGGAGATCAAGACTTACGGCTGACGAATACCTGAAAATTTATCAAGCAGCAGAATCATCACCATGTTGGCTCAGACTTGCAATGGAACTGGCTGTTGTTACCGGGCAACGAGTTGGTGATTTATGCGAAATGAAGTGGTCTGATATCGTAGATGGATATCTTTATGTCGAGCAAAGCAAAACAGGCGTAAAAATTGCCATCCCAACAGCATTGCATATTGATGCTCTCGGAATATCAATGAAGGAAACACTTGATAAATGCAAAGAGATTCTTGGCGGAGAAACCATAATTGCATCTACTCGTCGCGAACCGCTTTCATCCGGCACAGTATCAAGGTATTTTATGCGCGCACGAAAAGCATCAGGTCTTTCCTTCGAAGGGGATCCGCCTACCTTTCACGAGTTGCGCAGTTTGTCTGCAAGACTCTATGAGAAGCAGATAAGCGATAAGTTTGCTCAACATCTTCTCGGGCATAAGTCGGACACCATGGCATCACAGTATCGTGATGACAGAGGCAGGGAGTGGGACAAAATTGAAATCAAATAA
Enter frame number: -2
MGRRRSHERRDLPPNLYIRNNGYYCYRDPRTGKEFGLGRDRRIAITEAIQANIELFSGHKHKPLTARINSDNSVTLHSWLDRYEKILASRGIKQKTLINYMSKIKAIRRGLPDAPLEDITTKEIAAMLNGYIDEGKAASAKLIRSTLSDAFREAIAEGHITTNHVAATRAAKSEVRRSRLTADEYLKIYQAAESSPCWLRLAMELAVVTGQRVGDLCEMKWSDIVDGYLYVEQSKTGVKIAIPTALHIDALGISMKETLDKCKEILGGETIIASTRREPLSSGTVSRYFMRARKASGLSFEGDPPTFHELRSLSARLYEKQISDKFAQHLLGHKSDTMASQYRDDRGREWDKIEIK*

I want to make program like this

Ask the user for a file name in FASTA format. Open the file (while checking for errors. Input the frame number (+1, +2, +3, -1, -2, -3) from the user. Output the amino acid sequence when read from the input frame.

I don't know what to fix. If you know a good solution, please let me know.