old_contents: from django.db import models
  from time import time
  
  from hashid_field import HashidAutoField, HashidField
  
  
  class Artist(models.Model):
      id = HashidAutoField(primary_key=True, min_length=20)
      name = models.CharField(max_length=40)
  
      def __str__(self):
          return "{} ({})".format(self.name, self.id)
  
  
  class Record(models.Model):
      name = models.CharField(max_length=40)
      artist = models.ForeignKey(Artist, on_delete=models.CASCADE, null=True, blank=True, related_name="records")
      reference_id = HashidField()
      alternate_id = HashidField(salt="a different salt", null=True, blank=True)
      key = HashidField(min_length=10, alphabet="abcdlmnotuvwxyz123789", null=True, blank=True)
  
      def __str__(self):
          return "{} ({})".format(self.name, self.reference_id)
  
  
  class Track(models.Model):
      id = HashidAutoField(primary_key=True, allow_int_lookup=True, min_length=10, prefix='albumtrack:', salt="abcd", alphabet="abcdefghijklmnop")
  
  
  class RecordLabel(models.Model):
      def name_prefix(model_class, **kw):
          return model_class._meta.verbose_name.replace(' ', '_') + '/'
  
      id = HashidAutoField(primary_key=True, allow_int_lookup=True, prefix=name_prefix)
new_contents: from django.db import models
  
  from hashid_field import HashidAutoField, HashidField
  
  
  class Artist(models.Model):
      id = HashidAutoField(primary_key=True, min_length=20)
      name = models.CharField(max_length=40)
  
      def __str__(self):
          return "{} ({})".format(self.name, self.id)
  
  
  class Record(models.Model):
      name = models.CharField(max_length=40)
      artist = models.ForeignKey(Artist, on_delete=models.CASCADE, null=True, blank=True, related_name="records")
      reference_id = HashidField()
      alternate_id = HashidField(salt="a different salt", null=True, blank=True)
      key = HashidField(min_length=10, alphabet="abcdlmnotuvwxyz123789", null=True, blank=True)
  
      def __str__(self):
          return "{} ({})".format(self.name, self.reference_id)
  
  
  class Track(models.Model):
      id = HashidAutoField(primary_key=True, allow_int_lookup=True, min_length=10, prefix='albumtrack:', salt="abcd", alphabet="abcdefghijklmnop")
  
  
  class RecordLabel(models.Model):
      def name_prefix(model_class, **kw):
          return model_class._meta.verbose_name.replace(' ', '_') + '/'
  
      id = HashidAutoField(primary_key=True, allow_int_lookup=True, prefix=name_prefix)
subject: Remove unused import