django eyed3 script to add mp3 to database

I'm writing a script to add a genre artist and title of song to django project. Here are parts from my models

class GenreManager(models.Manager):
    def isGenreInDb(self,genre):
        try:
            genre=self.get(name__iexact=genre)
            return genre.id
        except Genre.DoesNotExist:
            return False
    def addGenreToDb(self,genre):
        new=Genre(name=genre)
        new.save()
        return new.id
class Genre(models.Model):
    name=models.CharField(max_length=100,unique=True)
    objects=GenreManager()
    def __unicode__(self):
        return self.name

class ArtistManager(models.Manager):
        #check if artist in in database and return True else return False
    def isArtistInDb(self,artist):
        try:
                artist=self.get(name__iexact=artist)
                return True
            except Artist.DoesNotExist:
                    return False
        def getArtistId(self,artist):
            try:
                temp=Artist.objects.get(name__iexact=artist)
                return temp.id
            except Artist.DoesNotExist:
                    return False  
        #add artist to db and return it's id
        def addArtist(self,artist):
            new=Artist(name=artist)
            new.save()
            return new.id

class Artist(models.Model):
    name=models.CharField(max_length=100,default="Unknown",unique=True)
    objects=ArtistManager()
    def __unicode__(self):
        return self.name
class Mp3Manager(models.Manager):
    #try to serch if a mp3 already exist and if not return False else return True
    def getMp3(self,artist,title):
        try:
            temp=Artist.objects.get(name__iexact=artist)
            q=self.get(artist=temp,title__iexact=title)
            return True
        except Mp3.DoesNotExist:
            return False


 class Mp3(models.Model):
     genre=models.ForeignKey('Genre')
     addedby=models.ForeignKey(User)
     artist=models.ForeignKey('Artist')
     title=models.CharField(max_length=30)
     valid=models.BooleanField(default=False)

location=models.CharField(max_length=200,unique=True)
length=models.CharField(max_length=10)

And here it script to adding mp3 to database. Script have access to my django app models

# additional variables
badFiles=0 # num of files which are causing problems

#check if values are set and non empty
def defined(value):
    try:
    if len(value)==0 or value==None:
        return False
    return True
    except TypeError:
    return False

#try to get artist or title using mutagen library
def mutagen(path,what):
    try:
    audio = ID3(path)
    if what=="artist": 
        return audio['TPE1'].text[0]
    else:
        return audio["TIT2"].text[0]
    except KeyError:
    return False

#try to get id3 tag using eyed3 module
def eyed3Fun(path):
    global genreLog,invalidLog,badFiles,statusLog
    try:
    trackInfo = eyeD3.Mp3AudioFile(path)
    tag = trackInfo.getTag()
    tag.link(path)
    artist=tag.getArtist()
    title=tag.getTitle()
    genre=tag.getGenre()
    time=trackInfo.getPlayTimeString() # assums that it always return a true value??
    results={}
    results['genre']=genre
    results['time']=time
    if defined(artist) and defined(title) == True: # if we have bouth artist and title
        results['artist']=artist
        results['title']=title
    if defined(title)==False:
        results['artist']=artist
        results['title']=False
    if defined(artist)==False:
        results['artist']=False
        results['title']=title
    return results
    except eyeD3.tag.GenreException as e:
    message="Problem while processing genre in %s \n" % path
    genreLog.write(message)
    statusLog.write("Problem with parsing tag\n")
    badFiles=badFiles+1
    return False
    except eyeD3.InvalidAudioFormatException as e:
    message="Invalid file in %s \n" % path
    invalidLog.write(message)
    statusLog.write("Invalid file type \n")
    badFiles=badFiles+1
    return False
    except AttributeError as e:
    message="can't read tag for %s  " % path + str(e) + "\n"
    pathLog.write(message)
    statusLog.write("Attribute error\n")
    badFiles=badFiles+1
    return False


def addToDatabase(path,artist,title,genre,time):
    global statusLog
    if genre==None: genreId=1 # if we don't know genre set to unknown
    elif Genre.objects.isGenreInDb(genre)==True: # if it already exsist
    temp=Genre.objects.get(name=genre)
    genreId=temp.id
    else: #if it is not in db we have to create it
    genreId=Genre.objects.addGenreToDb(genre)
    #artist part
    if  Artist.objects.isArtistInDb(artist)==True:
    artistId=Artist.objects.getArtistId(artist)
    else:
    artistId=Artist.objects.addArtist(artist)
    if Mp3.objects.getMp3(artist,title): # file exsist in database already skip
        statusLog.write("File already is in db abort\n\n")
        return
    mp3=Mp3(title=title,location=path,valid=True,length=time)
    mp3.genre=Genre.objects.get(id=genreId)
    mp3.artist=Artist.objects.get(id=artistId)
    mp3.addedby=User.objects.get(id=1) # have to be added bot in users table
    mp3.save()
    statusLog.write("Saved into db")

#this function is called when found valid mp3 file
def FoundMp3(path):
    global statusLog
    statusLog.write("Processing %s \n" % path)
    results=eyed3Fun(path)
    if not results : return # if we have a whatever exception in id3 than skip
    if not results['artist']: #if eye d3 can't get artist try to get using mutagen 
    temp=mutagen(path,"artist")
    if defined(temp):
        results['artist']=temp
    if not results['title']: # the same as above but for title开发者_如何学JAVA
    temp=mutagen(path,"title")
    if defined(temp)==True:
        results['title']=temp
    #know we should have all info about mp3 so add it to database
    if defined(results['artist']) and defined(results['title'])== True:
    statusLog.write(str(results))
    addToDatabase(path,results['artist'],results['title'],results['genre'],results['time'])
    statusLog.write("\n************\n")
    else:
    statusLog.write("Can't get artist or title\n")

#script starts
mp3Num=0 # num of mp3 files scanned
temp=os.walk('folder with music')
for root, dirs, files in temp:
    for i in files:
        if os.path.join(root,i):
            temp=os.path.splitext(i)
            temp[1].lower()
            if temp[1]=='.mp3':
                mp3Path=os.path.join(root,i)
        mp3Path=os.path.abspath(mp3Path)
                FoundMp3(mp3Path)
                mp3Num+=1
        else:
            print "Invalid path"

print " Found %d mp3 files" % mp3Num
print "Invalid files %d" % badFiles

And I have few problems which I can't solve. Sometimes it try do add a genre that is already in a database and second sometimes it crashing because of adding to database field genre with eyed3 instance not a valid id. I don't know how to solve these problems. I will appreciate any help. Thx in advance