We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Duplicate choices in shipping address
### What I'm trying to achieve
I'm trying to set shipping user for Russian user and there are duplicate values in "Oblast" selector.

### Steps to reproduce the problem
1. Create new shipping address
2. Country --> Russia
3. There are duplicated values in "Oblast" selector

### What I expected to happen
There are no duplicated values in "Oblast" selector

### Screenshots
What happens now
<img src="https://user-images.githubusercontent.com/13136992/53255369-8a239600-36d6-11e9-84a6-24a10b96a321.png" width="300">


What I expect to see
<img src="https://user-images.githubusercontent.com/13136992/53255400-99a2df00-36d6-11e9-8913-ecaec174487a.png" width="300">


**System information**
Operating system: Manjaro Linux
Browser: Google Chrome 72.0.3626.81


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `saleor/account/forms.py`
Content:
```
1 from captcha.fields import ReCaptchaField
2 from django import forms
3 from django.conf import settings
4 from django.contrib.auth import forms as django_forms, update_session_auth_hash
5 from django.utils.translation import pgettext, pgettext_lazy
6 from phonenumbers.phonenumberutil import country_code_for_region
7 
8 from ..account.models import User
9 from . import emails
10 from .i18n import AddressMetaForm, get_address_form_class
11 
12 
13 class FormWithReCaptcha(forms.BaseForm):
14     def __new__(cls, *args, **kwargs):
15         if settings.RECAPTCHA_PUBLIC_KEY and settings.RECAPTCHA_PRIVATE_KEY:
16             # insert a Google reCaptcha field inside the form
17             # note: label is empty, the reCaptcha is self-explanatory making
18             #       the form simpler for the user.
19             cls.base_fields['_captcha'] = ReCaptchaField(label='')
20         return super(FormWithReCaptcha, cls).__new__(cls)
21 
22 
23 def get_address_form(
24         data, country_code, initial=None, instance=None, **kwargs):
25     country_form = AddressMetaForm(data, initial=initial)
26     preview = False
27     if country_form.is_valid():
28         country_code = country_form.cleaned_data['country']
29         preview = country_form.cleaned_data['preview']
30 
31     if initial is None and country_code:
32         initial = {}
33     if country_code:
34         initial['phone'] = '+{}'.format(country_code_for_region(country_code))
35 
36     address_form_class = get_address_form_class(country_code)
37 
38     if not preview and instance is not None:
39         address_form_class = get_address_form_class(instance.country.code)
40         address_form = address_form_class(data, instance=instance, **kwargs)
41     else:
42         initial_address = (
43             initial if not preview
44             else data.dict() if data is not None else data)
45         address_form = address_form_class(
46             not preview and data or None,
47             initial=initial_address,
48             **kwargs)
49     return address_form, preview
50 
51 
52 class ChangePasswordForm(django_forms.PasswordChangeForm):
53     def __init__(self, *args, **kwargs):
54         super().__init__(*args, **kwargs)
55         self.fields['new_password1'].user = self.user
56         self.fields['old_password'].widget.attrs['placeholder'] = ''
57         self.fields['new_password1'].widget.attrs['placeholder'] = ''
58         del self.fields['new_password2']
59 
60 
61 def logout_on_password_change(request, user):
62     if (update_session_auth_hash is not None and
63             not settings.LOGOUT_ON_PASSWORD_CHANGE):
64         update_session_auth_hash(request, user)
65 
66 
67 class LoginForm(django_forms.AuthenticationForm, FormWithReCaptcha):
68     username = forms.EmailField(
69         label=pgettext('Form field', 'Email'), max_length=75)
70 
71     def __init__(self, request=None, *args, **kwargs):
72         super().__init__(request=request, *args, **kwargs)
73         if request:
74             email = request.GET.get('email')
75             if email:
76                 self.fields['username'].initial = email
77 
78 
79 class SignupForm(forms.ModelForm, FormWithReCaptcha):
80     password = forms.CharField(
81         widget=forms.PasswordInput,
82         label=pgettext('Password', 'Password'))
83     email = forms.EmailField(
84         label=pgettext('Email', 'Email'),
85         error_messages={
86             'unique': pgettext_lazy(
87                 'Registration error',
88                 'This email has already been registered.')})
89 
90     class Meta:
91         model = User
92         fields = ('email',)
93 
94     def __init__(self, *args, **kwargs):
95         super().__init__(*args, **kwargs)
96         if self._meta.model.USERNAME_FIELD in self.fields:
97             self.fields[self._meta.model.USERNAME_FIELD].widget.attrs.update(
98                 {'autofocus': ''})
99 
100     def save(self, request=None, commit=True):
101         user = super().save(commit=False)
102         password = self.cleaned_data['password']
103         user.set_password(password)
104         if commit:
105             user.save()
106         return user
107 
108 
109 class PasswordResetForm(django_forms.PasswordResetForm, FormWithReCaptcha):
110     """Allow resetting passwords.
111 
112     This subclass overrides sending emails to use templated email.
113     """
114 
115     def get_users(self, email):
116         active_users = User.objects.filter(email__iexact=email, is_active=True)
117         return active_users
118 
119     def send_mail(
120             self, subject_template_name, email_template_name, context,
121             from_email, to_email, html_email_template_name=None):
122         # Passing the user object to the Celery task throws an
123         # error "'User' is not JSON serializable". Since it's not used in our
124         # template, we remove it from the context.
125         del context['user']
126         emails.send_password_reset_email.delay(context, to_email)
127 
128 
129 class NameForm(forms.ModelForm):
130     class Meta:
131         model = User
132         fields = ['first_name', 'last_name']
133         labels = {
134             'first_name': pgettext_lazy(
135                 'Customer form: Given name field', 'Given name'),
136             'last_name': pgettext_lazy(
137                 'Customer form: Family name field', 'Family name')}
138
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/saleor/account/forms.py b/saleor/account/forms.py
--- a/saleor/account/forms.py
+++ b/saleor/account/forms.py
@@ -46,6 +46,11 @@
             not preview and data or None,
             initial=initial_address,
             **kwargs)
+
+    if hasattr(address_form.fields['country_area'], 'choices'):
+        choices = address_form.fields['country_area'].choices
+        choices = [(choice[1], choice[1]) for choice in choices]
+        address_form.fields['country_area'].choices = choices
     return address_form, preview

{"golden_diff": "diff --git a/saleor/account/forms.py b/saleor/account/forms.py\n--- a/saleor/account/forms.py\n+++ b/saleor/account/forms.py\n@@ -46,6 +46,11 @@\n             not preview and data or None,\n             initial=initial_address,\n             **kwargs)\n+\n+    if hasattr(address_form.fields['country_area'], 'choices'):\n+        choices = address_form.fields['country_area'].choices\n+        choices = [(choice[1], choice[1]) for choice in choices]\n+        address_form.fields['country_area'].choices = choices\n     return address_form, preview\n", "issue": "Duplicate choices in shipping address\n### What I'm trying to achieve\r\nI'm trying to set shipping user for Russian user and there are duplicate values in \"Oblast\" selector.\r\n\r\n### Steps to reproduce the problem\r\n1. Create new shipping address\r\n2. Country --> Russia\r\n3. There are duplicated values in \"Oblast\" selector\r\n\r\n### What I expected to happen\r\nThere are no duplicated values in \"Oblast\" selector\r\n\r\n### Screenshots\r\nWhat happens now\r\n<img src=\"https://user-images.githubusercontent.com/13136992/53255369-8a239600-36d6-11e9-84a6-24a10b96a321.png\" width=\"300\">\r\n\r\n\r\nWhat I expect to see\r\n<img src=\"https://user-images.githubusercontent.com/13136992/53255400-99a2df00-36d6-11e9-8913-ecaec174487a.png\" width=\"300\">\r\n\r\n\r\n**System information**\r\nOperating system: Manjaro Linux\r\nBrowser: Google Chrome 72.0.3626.81\r\n\n", "before_files": [{"content": "from captcha.fields import ReCaptchaField\nfrom django import forms\nfrom django.conf import settings\nfrom django.contrib.auth import forms as django_forms, update_session_auth_hash\nfrom django.utils.translation import pgettext, pgettext_lazy\nfrom phonenumbers.phonenumberutil import country_code_for_region\n\nfrom ..account.models import User\nfrom . import emails\nfrom .i18n import AddressMetaForm, get_address_form_class\n\n\nclass FormWithReCaptcha(forms.BaseForm):\n    def __new__(cls, *args, **kwargs):\n        if settings.RECAPTCHA_PUBLIC_KEY and settings.RECAPTCHA_PRIVATE_KEY:\n            # insert a Google reCaptcha field inside the form\n            # note: label is empty, the reCaptcha is self-explanatory making\n            #       the form simpler for the user.\n            cls.base_fields['_captcha'] = ReCaptchaField(label='')\n        return super(FormWithReCaptcha, cls).__new__(cls)\n\n\ndef get_address_form(\n        data, country_code, initial=None, instance=None, **kwargs):\n    country_form = AddressMetaForm(data, initial=initial)\n    preview = False\n    if country_form.is_valid():\n        country_code = country_form.cleaned_data['country']\n        preview = country_form.cleaned_data['preview']\n\n    if initial is None and country_code:\n        initial = {}\n    if country_code:\n        initial['phone'] = '+{}'.format(country_code_for_region(country_code))\n\n    address_form_class = get_address_form_class(country_code)\n\n    if not preview and instance is not None:\n        address_form_class = get_address_form_class(instance.country.code)\n        address_form = address_form_class(data, instance=instance, **kwargs)\n    else:\n        initial_address = (\n            initial if not preview\n            else data.dict() if data is not None else data)\n        address_form = address_form_class(\n            not preview and data or None,\n            initial=initial_address,\n            **kwargs)\n    return address_form, preview\n\n\nclass ChangePasswordForm(django_forms.PasswordChangeForm):\n    def __init__(self, *args, **kwargs):\n        super().__init__(*args, **kwargs)\n        self.fields['new_password1'].user = self.user\n        self.fields['old_password'].widget.attrs['placeholder'] = ''\n        self.fields['new_password1'].widget.attrs['placeholder'] = ''\n        del self.fields['new_password2']\n\n\ndef logout_on_password_change(request, user):\n    if (update_session_auth_hash is not None and\n            not settings.LOGOUT_ON_PASSWORD_CHANGE):\n        update_session_auth_hash(request, user)\n\n\nclass LoginForm(django_forms.AuthenticationForm, FormWithReCaptcha):\n    username = forms.EmailField(\n        label=pgettext('Form field', 'Email'), max_length=75)\n\n    def __init__(self, request=None, *args, **kwargs):\n        super().__init__(request=request, *args, **kwargs)\n        if request:\n            email = request.GET.get('email')\n            if email:\n                self.fields['username'].initial = email\n\n\nclass SignupForm(forms.ModelForm, FormWithReCaptcha):\n    password = forms.CharField(\n        widget=forms.PasswordInput,\n        label=pgettext('Password', 'Password'))\n    email = forms.EmailField(\n        label=pgettext('Email', 'Email'),\n        error_messages={\n            'unique': pgettext_lazy(\n                'Registration error',\n                'This email has already been registered.')})\n\n    class Meta:\n        model = User\n        fields = ('email',)\n\n    def __init__(self, *args, **kwargs):\n        super().__init__(*args, **kwargs)\n        if self._meta.model.USERNAME_FIELD in self.fields:\n            self.fields[self._meta.model.USERNAME_FIELD].widget.attrs.update(\n                {'autofocus': ''})\n\n    def save(self, request=None, commit=True):\n        user = super().save(commit=False)\n        password = self.cleaned_data['password']\n        user.set_password(password)\n        if commit:\n            user.save()\n        return user\n\n\nclass PasswordResetForm(django_forms.PasswordResetForm, FormWithReCaptcha):\n    \"\"\"Allow resetting passwords.\n\n    This subclass overrides sending emails to use templated email.\n    \"\"\"\n\n    def get_users(self, email):\n        active_users = User.objects.filter(email__iexact=email, is_active=True)\n        return active_users\n\n    def send_mail(\n            self, subject_template_name, email_template_name, context,\n            from_email, to_email, html_email_template_name=None):\n        # Passing the user object to the Celery task throws an\n        # error \"'User' is not JSON serializable\". Since it's not used in our\n        # template, we remove it from the context.\n        del context['user']\n        emails.send_password_reset_email.delay(context, to_email)\n\n\nclass NameForm(forms.ModelForm):\n    class Meta:\n        model = User\n        fields = ['first_name', 'last_name']\n        labels = {\n            'first_name': pgettext_lazy(\n                'Customer form: Given name field', 'Given name'),\n            'last_name': pgettext_lazy(\n                'Customer form: Family name field', 'Family name')}\n", "path": "saleor/account/forms.py"}], "after_files": [{"content": "from captcha.fields import ReCaptchaField\nfrom django import forms\nfrom django.conf import settings\nfrom django.contrib.auth import forms as django_forms, update_session_auth_hash\nfrom django.utils.translation import pgettext, pgettext_lazy\nfrom phonenumbers.phonenumberutil import country_code_for_region\n\nfrom ..account.models import User\nfrom . import emails\nfrom .i18n import AddressMetaForm, get_address_form_class\n\n\nclass FormWithReCaptcha(forms.BaseForm):\n    def __new__(cls, *args, **kwargs):\n        if settings.RECAPTCHA_PUBLIC_KEY and settings.RECAPTCHA_PRIVATE_KEY:\n            # insert a Google reCaptcha field inside the form\n            # note: label is empty, the reCaptcha is self-explanatory making\n            #       the form simpler for the user.\n            cls.base_fields['_captcha'] = ReCaptchaField(label='')\n        return super(FormWithReCaptcha, cls).__new__(cls)\n\n\ndef get_address_form(\n        data, country_code, initial=None, instance=None, **kwargs):\n    country_form = AddressMetaForm(data, initial=initial)\n    preview = False\n    if country_form.is_valid():\n        country_code = country_form.cleaned_data['country']\n        preview = country_form.cleaned_data['preview']\n\n    if initial is None and country_code:\n        initial = {}\n    if country_code:\n        initial['phone'] = '+{}'.format(country_code_for_region(country_code))\n\n    address_form_class = get_address_form_class(country_code)\n\n    if not preview and instance is not None:\n        address_form_class = get_address_form_class(instance.country.code)\n        address_form = address_form_class(data, instance=instance, **kwargs)\n    else:\n        initial_address = (\n            initial if not preview\n            else data.dict() if data is not None else data)\n        address_form = address_form_class(\n            not preview and data or None,\n            initial=initial_address,\n            **kwargs)\n\n    if hasattr(address_form.fields['country_area'], 'choices'):\n        choices = address_form.fields['country_area'].choices\n        choices = [(choice[1], choice[1]) for choice in choices]\n        address_form.fields['country_area'].choices = choices\n    return address_form, preview\n\n\nclass ChangePasswordForm(django_forms.PasswordChangeForm):\n    def __init__(self, *args, **kwargs):\n        super().__init__(*args, **kwargs)\n        self.fields['new_password1'].user = self.user\n        self.fields['old_password'].widget.attrs['placeholder'] = ''\n        self.fields['new_password1'].widget.attrs['placeholder'] = ''\n        del self.fields['new_password2']\n\n\ndef logout_on_password_change(request, user):\n    if (update_session_auth_hash is not None and\n            not settings.LOGOUT_ON_PASSWORD_CHANGE):\n        update_session_auth_hash(request, user)\n\n\nclass LoginForm(django_forms.AuthenticationForm, FormWithReCaptcha):\n    username = forms.EmailField(\n        label=pgettext('Form field', 'Email'), max_length=75)\n\n    def __init__(self, request=None, *args, **kwargs):\n        super().__init__(request=request, *args, **kwargs)\n        if request:\n            email = request.GET.get('email')\n            if email:\n                self.fields['username'].initial = email\n\n\nclass SignupForm(forms.ModelForm, FormWithReCaptcha):\n    password = forms.CharField(\n        widget=forms.PasswordInput,\n        label=pgettext('Password', 'Password'))\n    email = forms.EmailField(\n        label=pgettext('Email', 'Email'),\n        error_messages={\n            'unique': pgettext_lazy(\n                'Registration error',\n                'This email has already been registered.')})\n\n    class Meta:\n        model = User\n        fields = ('email',)\n\n    def __init__(self, *args, **kwargs):\n        super().__init__(*args, **kwargs)\n        if self._meta.model.USERNAME_FIELD in self.fields:\n            self.fields[self._meta.model.USERNAME_FIELD].widget.attrs.update(\n                {'autofocus': ''})\n\n    def save(self, request=None, commit=True):\n        user = super().save(commit=False)\n        password = self.cleaned_data['password']\n        user.set_password(password)\n        if commit:\n            user.save()\n        return user\n\n\nclass PasswordResetForm(django_forms.PasswordResetForm, FormWithReCaptcha):\n    \"\"\"Allow resetting passwords.\n\n    This subclass overrides sending emails to use templated email.\n    \"\"\"\n\n    def get_users(self, email):\n        active_users = User.objects.filter(email__iexact=email, is_active=True)\n        return active_users\n\n    def send_mail(\n            self, subject_template_name, email_template_name, context,\n            from_email, to_email, html_email_template_name=None):\n        # Passing the user object to the Celery task throws an\n        # error \"'User' is not JSON serializable\". Since it's not used in our\n        # template, we remove it from the context.\n        del context['user']\n        emails.send_password_reset_email.delay(context, to_email)\n\n\nclass NameForm(forms.ModelForm):\n    class Meta:\n        model = User\n        fields = ['first_name', 'last_name']\n        labels = {\n            'first_name': pgettext_lazy(\n                'Customer form: Given name field', 'Given name'),\n            'last_name': pgettext_lazy(\n                'Customer form: Family name field', 'Family name')}\n", "path": "saleor/account/forms.py"}]}