diff --git a/eav/fields.py b/eav/fields.py
index f573332..3377730 100644
--- a/eav/fields.py
+++ b/eav/fields.py
@@ -2,7 +2,7 @@ import re
 
 from django.core.exceptions import ValidationError
 from django.db import models
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class EavSlugField(models.SlugField):
diff --git a/eav/forms.py b/eav/forms.py
index b1f97b1..e750b2b 100644
--- a/eav/forms.py
+++ b/eav/forms.py
@@ -5,7 +5,7 @@ from copy import deepcopy
 from django.contrib.admin.widgets import AdminSplitDateTime
 from django.forms import (BooleanField, CharField, ChoiceField, DateTimeField,
                           FloatField, IntegerField, ModelForm)
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 class BaseDynamicEntityForm(ModelForm):
diff --git a/eav/migrations/0001_initial.py b/eav/migrations/0001_initial.py
index 7417deb..686440d 100644
--- a/eav/migrations/0001_initial.py
+++ b/eav/migrations/0001_initial.py
@@ -55,7 +55,7 @@ class Migration(migrations.Migration):
                 ('value_float', models.FloatField(blank=True, null=True)),
                 ('value_int', models.IntegerField(blank=True, null=True)),
                 ('value_date', models.DateTimeField(blank=True, null=True)),
-                ('value_bool', models.NullBooleanField()),
+                ('value_bool', models.BooleanField(null=True)),
                 ('generic_value_id', models.IntegerField(blank=True, null=True)),
                 ('created', models.DateTimeField(default=django.utils.timezone.now, verbose_name='Created')),
                 ('modified', models.DateTimeField(auto_now=True, verbose_name='Modified')),
diff --git a/eav/models.py b/eav/models.py
index ec5e680..234c39d 100644
--- a/eav/models.py
+++ b/eav/models.py
@@ -19,7 +19,7 @@ from django.core.exceptions import ValidationError
 from django.db import models
 from django.db.models.base import ModelBase
 from django.utils import timezone
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 from .validators import validate_decimal
 from .validators import validate_enum_multi
@@ -418,7 +418,7 @@ class Value(models.Model):
     value_decimal = models.DecimalField(blank = True, null = True, max_digits = 14, decimal_places = 2)
     value_int     = models.IntegerField(blank = True, null = True)
     value_date    = models.DateTimeField(blank = True, null = True)
-    value_bool    = models.NullBooleanField(blank = True, null = True)
+    value_bool    = models.BooleanField(null=True)
 
     value_enum  = models.ForeignKey(
         EnumValue,
diff --git a/eav/validators.py b/eav/validators.py
index dd0586e..f01a8c7 100644
--- a/eav/validators.py
+++ b/eav/validators.py
@@ -15,7 +15,7 @@ import datetime
 
 from django.core.exceptions import ValidationError
 from django.db import models
-from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import gettext_lazy as _
 
 
 def validate_text(value):