DNA to Amino Acid

#This code will convert sequences into amino acids by using the gencode table below.
#Jennifer Owen
#Stephanie Perez
#Lisa DiMusto



import sys
import re

infile = 'practice1.fa'

class dnatranslate:

    def __init__(self,infile,sequence=None,people=None):
        self.infile = infile
        self.sequence = ''
        self.protein=''
        self.start = ''
        self.sequence_start = ''


    def openfile(self):
        with open ('practice1.fa','r') as file:
            for line in file.readlines():
                aa=re.sub('-','',line)
                #print (aa)
                if line.startswith('>'):
                    self.protein = line.rstrip('\n')+ '\n'
                    #print(self.protein)
                else:
                    self.sequence += line


    def translate_dna(self):
        gencode = {
            'ATA':'I', 'ATC':'I', 'ATT':'I', 'ATG':'M',
            'ACA':'T', 'ACC':'T', 'ACG':'T', 'ACT':'T',
            'AAC':'N', 'AAT':'N', 'AAA':'K', 'AAG':'K',
            'AGC':'S', 'AGT':'S', 'AGA':'R', 'AGG':'R',
            'CTA':'L', 'CTC':'L', 'CTG':'L', 'CTT':'L',
            'CCA':'P', 'CCC':'P', 'CCG':'P', 'CCT':'P',
            'CAC':'H', 'CAT':'H', 'CAA':'Q', 'CAG':'Q',
            'CGA':'R', 'CGC':'R', 'CGG':'R', 'CGT':'R',
            'GTA':'V', 'GTC':'V', 'GTG':'V', 'GTT':'V',
            'GCA':'A', 'GCC':'A', 'GCG':'A', 'GCT':'A',
            'GAC':'D', 'GAT':'D', 'GAA':'E', 'GAG':'E',
            'GGA':'G', 'GGC':'G', 'GGG':'G', 'GGT':'G',
            'TCA':'S', 'TCC':'S', 'TCG':'S', 'TCT':'S',
            'TTC':'F', 'TTT':'F', 'TTA':'L', 'TTG':'L',
            'TAC':'Y', 'TAT':'Y', 'TAA':'_', 'TAG':'_',
            'TGC':'C', 'TGT':'C', 'TGA':'_', 'TGG':'W'}

        self.start = self.sequence.find('ATG')
        self.sequence_start = self.sequence[int(self.start):]
        #self.stop = self.sequence_start.find('TAA')
        #self.cds = str(self.sequence_start[:int(self.stop)+3])

        for n in range(0,len(self.sequence_start),3):
            if self.sequence_start[n:n+3] in gencode:
                self.protein += gencode[self.sequence_start[n:n+3]]
        return self.protein
        #print(self.protein)



    def outfile(self): # need to work on this part
        out = open('practice.out.fa','w')
        out.write(self.protein)
        out.close



transl = dnatranslate(infile)
transl.openfile()
transl.translate_dna()
transl.outfile()