We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
UnicodeEncodeError with ProjectCustomField
```python

  File "django/core/handlers/base.py", line 111, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "django/views/decorators/csrf.py", line 57, in wrapped_view
    return view_func(*args, **kwargs)
  File "django/views/generic/base.py", line 69, in view
    return self.dispatch(request, *args, **kwargs)
  File "rest_framework/views.py", line 466, in dispatch
    response = self.handle_exception(exc)
  File "rest_framework/views.py", line 463, in dispatch
    response = handler(request, *args, **kwargs)
  File "rest_framework/decorators.py", line 53, in handler
    return func(*args, **kwargs)
  File "akvo/rest/views/project_editor.py", line 576, in project_editor
    'changes': log_changes(changes, user, project),
  File "akvo/rest/views/project_editor.py", line 92, in log_changes
    object_repr=obj.__unicode__(),
  File "akvo/rsr/models/custom_field.py", line 77, in __unicode__
    return u'%s' % str(self.value)
```

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `akvo/rsr/models/custom_field.py`
Content:
```
1 # -*- coding: utf-8 -*-
2 
3 # Akvo RSR is covered by the GNU Affero General Public License.
4 # See more details in the license.txt file located at the root folder of the Akvo RSR module.
5 # For additional details on the GNU license please see < http://www.gnu.org/licenses/agpl.html >.
6 
7 
8 from django.db import models
9 from django.utils.translation import ugettext_lazy as _
10 
11 from ..fields import ValidXMLCharField, ValidXMLTextField
12 
13 
14 class ProjectCustomField(models.Model):
15     """
16     Custom fields make it possible for partner to specify additional fields. When specified for a
17     project, the fields will appear in the admin (under the specified section) and can then be
18     filled in.
19 
20     Custom fields for a project, linking the project to its' custom fields.
21 
22     Name: name of the custom field (label in the admin)
23     Section: the section in the admin where the field should be added
24     Maxlength: the maximum number of characters of the field
25     Help text: the help text belonging to the field
26     Value: the value which can be filled in the project admin.
27     """
28     SECTIONS = (
29         (1, _(u'01 - General information')),
30         (2, _(u'02 - Contact information')),
31         (3, _(u'03 - Project partners')),
32         (4, _(u'04 - Project descriptions')),
33         (5, _(u'05 - Results and indicators')),
34         (6, _(u'06 - Finance')),
35         (7, _(u'07 - Project locations')),
36         (8, _(u'08 - Project focus')),
37         (9, _(u'09 - Links and documents')),
38         (10, _(u'10 - Project comments')),
39     )
40 
41     TYPES = (
42         ('text', _(u'Text')),
43         ('boolean', _(u'Checkbox')),
44     )
45 
46     project = models.ForeignKey('Project', verbose_name=_(u'project'), related_name='custom_fields')
47     name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))
48     section = models.IntegerField(
49         _(u'admin section'), choices=SECTIONS,
50         help_text=_(u'Select the section of the admin where the custom field should be displayed')
51     )
52     max_characters = models.IntegerField(
53         _(u'maximum characters'), blank=True, null=True,
54         help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '
55                     u'Leave empty or fill in 0 if there is no character limit.')
56     )
57     help_text = ValidXMLTextField(
58         _(u'help text'), max_length=1000, blank=True,
59         help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '
60                     u'there is no need for a help text. (max 1000 characters)')
61     )
62     value = ValidXMLTextField(_(u'value'), blank=True)
63     mandatory = models.BooleanField(_(u'mandatory'), default=False,
64                                     help_text=_(u'Indicate whether this field is mandatory or not'))
65     order = models.PositiveSmallIntegerField(
66         _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '
67                                  u'project editor. Must be a positive number, and the lowest '
68                                  u'number will be shown on top.')
69     )
70     type = ValidXMLCharField(
71         _(u'type'), max_length=20, choices=TYPES, default='text',
72         help_text=_(u'Select the type of custom field. Text will show a text area in the project '
73                     u'editor, and checkbox will show a checkbox.')
74     )
75 
76     def __unicode__(self):
77         return u'%s' % str(self.value)
78 
79 
80 class OrganisationCustomField(models.Model):
81     """
82     Custom fields make it possible for partner to specify additional fields. When specified for a
83     project, the fields will appear in the admin (under the specified section) and can then be
84     filled in.
85 
86     Custom fields for an organisation, linking the organisation to its' custom fields.
87 
88     These custom fields will be used for the projects whenever a user of the organisation
89     creates a new project.
90 
91     Name: name of the custom field (label in the admin)
92     Section: the section in the admin where the field should be added
93     Maxlength: the maximum number of characters of the field
94     Help text: the help text belonging to the field
95     """
96     SECTIONS = (
97         (1, _(u'01 - General information')),
98         (2, _(u'02 - Contact information')),
99         (3, _(u'03 - Project partners')),
100         (4, _(u'04 - Project descriptions')),
101         (5, _(u'05 - Results and indicators')),
102         (6, _(u'06 - Finance')),
103         (7, _(u'07 - Project locations')),
104         (8, _(u'08 - Project focus')),
105         (9, _(u'09 - Links and documents')),
106         (10, _(u'10 - Project comments')),
107     )
108 
109     TYPES = (
110         ('text', _(u'Text')),
111         ('boolean', _(u'Checkbox')),
112     )
113 
114     organisation = models.ForeignKey(
115         'Organisation', verbose_name=_(u'organisation'), related_name='custom_fields'
116     )
117     name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))
118     section = models.IntegerField(
119         _(u'admin section'), choices=SECTIONS,
120         help_text=_(u'Select the section of the admin where the custom field should be displayed')
121     )
122     max_characters = models.IntegerField(
123         _(u'maximum characters'), blank=True, null=True,
124         help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '
125                     u'Leave empty or fill in 0 if there is no character limit.')
126     )
127     help_text = ValidXMLTextField(
128         _(u'help text'), max_length=1000, blank=True,
129         help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '
130                     u'there is no need for a help text. (max 1000 characters)')
131     )
132     mandatory = models.BooleanField(_(u'mandatory'), default=False,
133                                     help_text=_(u'Indicate whether this field is mandatory or not'))
134     order = models.PositiveSmallIntegerField(
135         _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '
136                                  u'project editor. Must be a positive number, and the lowest '
137                                  u'number will be shown on top.')
138     )
139     type = ValidXMLCharField(
140         _(u'type'), max_length=20, choices=TYPES, default='text',
141         help_text=_(u'Select the type of custom field. Text will show a text area in the project '
142                     u'editor, and checkbox will show a checkbox.')
143     )
```
--- 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/akvo/rsr/models/custom_field.py b/akvo/rsr/models/custom_field.py
--- a/akvo/rsr/models/custom_field.py
+++ b/akvo/rsr/models/custom_field.py
@@ -74,7 +74,7 @@
     )
 
     def __unicode__(self):
-        return u'%s' % str(self.value)
+        return u'%s' % self.value
 
 
 class OrganisationCustomField(models.Model):
@@ -140,4 +140,4 @@
         _(u'type'), max_length=20, choices=TYPES, default='text',
         help_text=_(u'Select the type of custom field. Text will show a text area in the project '
                     u'editor, and checkbox will show a checkbox.')
-    )
\ No newline at end of file
+    )

{"golden_diff": "diff --git a/akvo/rsr/models/custom_field.py b/akvo/rsr/models/custom_field.py\n--- a/akvo/rsr/models/custom_field.py\n+++ b/akvo/rsr/models/custom_field.py\n@@ -74,7 +74,7 @@\n     )\n \n     def __unicode__(self):\n-        return u'%s' % str(self.value)\n+        return u'%s' % self.value\n \n \n class OrganisationCustomField(models.Model):\n@@ -140,4 +140,4 @@\n         _(u'type'), max_length=20, choices=TYPES, default='text',\n         help_text=_(u'Select the type of custom field. Text will show a text area in the project '\n                     u'editor, and checkbox will show a checkbox.')\n-    )\n\\ No newline at end of file\n+    )\n", "issue": "UnicodeEncodeError with ProjectCustomField\n```python\r\n\r\n  File \"django/core/handlers/base.py\", line 111, in get_response\r\n    response = wrapped_callback(request, *callback_args, **callback_kwargs)\r\n  File \"django/views/decorators/csrf.py\", line 57, in wrapped_view\r\n    return view_func(*args, **kwargs)\r\n  File \"django/views/generic/base.py\", line 69, in view\r\n    return self.dispatch(request, *args, **kwargs)\r\n  File \"rest_framework/views.py\", line 466, in dispatch\r\n    response = self.handle_exception(exc)\r\n  File \"rest_framework/views.py\", line 463, in dispatch\r\n    response = handler(request, *args, **kwargs)\r\n  File \"rest_framework/decorators.py\", line 53, in handler\r\n    return func(*args, **kwargs)\r\n  File \"akvo/rest/views/project_editor.py\", line 576, in project_editor\r\n    'changes': log_changes(changes, user, project),\r\n  File \"akvo/rest/views/project_editor.py\", line 92, in log_changes\r\n    object_repr=obj.__unicode__(),\r\n  File \"akvo/rsr/models/custom_field.py\", line 77, in __unicode__\r\n    return u'%s' % str(self.value)\r\n```\n", "before_files": [{"content": "# -*- coding: utf-8 -*-\n\n# Akvo RSR is covered by the GNU Affero General Public License.\n# See more details in the license.txt file located at the root folder of the Akvo RSR module.\n# For additional details on the GNU license please see < http://www.gnu.org/licenses/agpl.html >.\n\n\nfrom django.db import models\nfrom django.utils.translation import ugettext_lazy as _\n\nfrom ..fields import ValidXMLCharField, ValidXMLTextField\n\n\nclass ProjectCustomField(models.Model):\n    \"\"\"\n    Custom fields make it possible for partner to specify additional fields. When specified for a\n    project, the fields will appear in the admin (under the specified section) and can then be\n    filled in.\n\n    Custom fields for a project, linking the project to its' custom fields.\n\n    Name: name of the custom field (label in the admin)\n    Section: the section in the admin where the field should be added\n    Maxlength: the maximum number of characters of the field\n    Help text: the help text belonging to the field\n    Value: the value which can be filled in the project admin.\n    \"\"\"\n    SECTIONS = (\n        (1, _(u'01 - General information')),\n        (2, _(u'02 - Contact information')),\n        (3, _(u'03 - Project partners')),\n        (4, _(u'04 - Project descriptions')),\n        (5, _(u'05 - Results and indicators')),\n        (6, _(u'06 - Finance')),\n        (7, _(u'07 - Project locations')),\n        (8, _(u'08 - Project focus')),\n        (9, _(u'09 - Links and documents')),\n        (10, _(u'10 - Project comments')),\n    )\n\n    TYPES = (\n        ('text', _(u'Text')),\n        ('boolean', _(u'Checkbox')),\n    )\n\n    project = models.ForeignKey('Project', verbose_name=_(u'project'), related_name='custom_fields')\n    name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))\n    section = models.IntegerField(\n        _(u'admin section'), choices=SECTIONS,\n        help_text=_(u'Select the section of the admin where the custom field should be displayed')\n    )\n    max_characters = models.IntegerField(\n        _(u'maximum characters'), blank=True, null=True,\n        help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '\n                    u'Leave empty or fill in 0 if there is no character limit.')\n    )\n    help_text = ValidXMLTextField(\n        _(u'help text'), max_length=1000, blank=True,\n        help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '\n                    u'there is no need for a help text. (max 1000 characters)')\n    )\n    value = ValidXMLTextField(_(u'value'), blank=True)\n    mandatory = models.BooleanField(_(u'mandatory'), default=False,\n                                    help_text=_(u'Indicate whether this field is mandatory or not'))\n    order = models.PositiveSmallIntegerField(\n        _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '\n                                 u'project editor. Must be a positive number, and the lowest '\n                                 u'number will be shown on top.')\n    )\n    type = ValidXMLCharField(\n        _(u'type'), max_length=20, choices=TYPES, default='text',\n        help_text=_(u'Select the type of custom field. Text will show a text area in the project '\n                    u'editor, and checkbox will show a checkbox.')\n    )\n\n    def __unicode__(self):\n        return u'%s' % str(self.value)\n\n\nclass OrganisationCustomField(models.Model):\n    \"\"\"\n    Custom fields make it possible for partner to specify additional fields. When specified for a\n    project, the fields will appear in the admin (under the specified section) and can then be\n    filled in.\n\n    Custom fields for an organisation, linking the organisation to its' custom fields.\n\n    These custom fields will be used for the projects whenever a user of the organisation\n    creates a new project.\n\n    Name: name of the custom field (label in the admin)\n    Section: the section in the admin where the field should be added\n    Maxlength: the maximum number of characters of the field\n    Help text: the help text belonging to the field\n    \"\"\"\n    SECTIONS = (\n        (1, _(u'01 - General information')),\n        (2, _(u'02 - Contact information')),\n        (3, _(u'03 - Project partners')),\n        (4, _(u'04 - Project descriptions')),\n        (5, _(u'05 - Results and indicators')),\n        (6, _(u'06 - Finance')),\n        (7, _(u'07 - Project locations')),\n        (8, _(u'08 - Project focus')),\n        (9, _(u'09 - Links and documents')),\n        (10, _(u'10 - Project comments')),\n    )\n\n    TYPES = (\n        ('text', _(u'Text')),\n        ('boolean', _(u'Checkbox')),\n    )\n\n    organisation = models.ForeignKey(\n        'Organisation', verbose_name=_(u'organisation'), related_name='custom_fields'\n    )\n    name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))\n    section = models.IntegerField(\n        _(u'admin section'), choices=SECTIONS,\n        help_text=_(u'Select the section of the admin where the custom field should be displayed')\n    )\n    max_characters = models.IntegerField(\n        _(u'maximum characters'), blank=True, null=True,\n        help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '\n                    u'Leave empty or fill in 0 if there is no character limit.')\n    )\n    help_text = ValidXMLTextField(\n        _(u'help text'), max_length=1000, blank=True,\n        help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '\n                    u'there is no need for a help text. (max 1000 characters)')\n    )\n    mandatory = models.BooleanField(_(u'mandatory'), default=False,\n                                    help_text=_(u'Indicate whether this field is mandatory or not'))\n    order = models.PositiveSmallIntegerField(\n        _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '\n                                 u'project editor. Must be a positive number, and the lowest '\n                                 u'number will be shown on top.')\n    )\n    type = ValidXMLCharField(\n        _(u'type'), max_length=20, choices=TYPES, default='text',\n        help_text=_(u'Select the type of custom field. Text will show a text area in the project '\n                    u'editor, and checkbox will show a checkbox.')\n    )", "path": "akvo/rsr/models/custom_field.py"}], "after_files": [{"content": "# -*- coding: utf-8 -*-\n\n# Akvo RSR is covered by the GNU Affero General Public License.\n# See more details in the license.txt file located at the root folder of the Akvo RSR module.\n# For additional details on the GNU license please see < http://www.gnu.org/licenses/agpl.html >.\n\n\nfrom django.db import models\nfrom django.utils.translation import ugettext_lazy as _\n\nfrom ..fields import ValidXMLCharField, ValidXMLTextField\n\n\nclass ProjectCustomField(models.Model):\n    \"\"\"\n    Custom fields make it possible for partner to specify additional fields. When specified for a\n    project, the fields will appear in the admin (under the specified section) and can then be\n    filled in.\n\n    Custom fields for a project, linking the project to its' custom fields.\n\n    Name: name of the custom field (label in the admin)\n    Section: the section in the admin where the field should be added\n    Maxlength: the maximum number of characters of the field\n    Help text: the help text belonging to the field\n    Value: the value which can be filled in the project admin.\n    \"\"\"\n    SECTIONS = (\n        (1, _(u'01 - General information')),\n        (2, _(u'02 - Contact information')),\n        (3, _(u'03 - Project partners')),\n        (4, _(u'04 - Project descriptions')),\n        (5, _(u'05 - Results and indicators')),\n        (6, _(u'06 - Finance')),\n        (7, _(u'07 - Project locations')),\n        (8, _(u'08 - Project focus')),\n        (9, _(u'09 - Links and documents')),\n        (10, _(u'10 - Project comments')),\n    )\n\n    TYPES = (\n        ('text', _(u'Text')),\n        ('boolean', _(u'Checkbox')),\n    )\n\n    project = models.ForeignKey('Project', verbose_name=_(u'project'), related_name='custom_fields')\n    name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))\n    section = models.IntegerField(\n        _(u'admin section'), choices=SECTIONS,\n        help_text=_(u'Select the section of the admin where the custom field should be displayed')\n    )\n    max_characters = models.IntegerField(\n        _(u'maximum characters'), blank=True, null=True,\n        help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '\n                    u'Leave empty or fill in 0 if there is no character limit.')\n    )\n    help_text = ValidXMLTextField(\n        _(u'help text'), max_length=1000, blank=True,\n        help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '\n                    u'there is no need for a help text. (max 1000 characters)')\n    )\n    value = ValidXMLTextField(_(u'value'), blank=True)\n    mandatory = models.BooleanField(_(u'mandatory'), default=False,\n                                    help_text=_(u'Indicate whether this field is mandatory or not'))\n    order = models.PositiveSmallIntegerField(\n        _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '\n                                 u'project editor. Must be a positive number, and the lowest '\n                                 u'number will be shown on top.')\n    )\n    type = ValidXMLCharField(\n        _(u'type'), max_length=20, choices=TYPES, default='text',\n        help_text=_(u'Select the type of custom field. Text will show a text area in the project '\n                    u'editor, and checkbox will show a checkbox.')\n    )\n\n    def __unicode__(self):\n        return u'%s' % self.value\n\n\nclass OrganisationCustomField(models.Model):\n    \"\"\"\n    Custom fields make it possible for partner to specify additional fields. When specified for a\n    project, the fields will appear in the admin (under the specified section) and can then be\n    filled in.\n\n    Custom fields for an organisation, linking the organisation to its' custom fields.\n\n    These custom fields will be used for the projects whenever a user of the organisation\n    creates a new project.\n\n    Name: name of the custom field (label in the admin)\n    Section: the section in the admin where the field should be added\n    Maxlength: the maximum number of characters of the field\n    Help text: the help text belonging to the field\n    \"\"\"\n    SECTIONS = (\n        (1, _(u'01 - General information')),\n        (2, _(u'02 - Contact information')),\n        (3, _(u'03 - Project partners')),\n        (4, _(u'04 - Project descriptions')),\n        (5, _(u'05 - Results and indicators')),\n        (6, _(u'06 - Finance')),\n        (7, _(u'07 - Project locations')),\n        (8, _(u'08 - Project focus')),\n        (9, _(u'09 - Links and documents')),\n        (10, _(u'10 - Project comments')),\n    )\n\n    TYPES = (\n        ('text', _(u'Text')),\n        ('boolean', _(u'Checkbox')),\n    )\n\n    organisation = models.ForeignKey(\n        'Organisation', verbose_name=_(u'organisation'), related_name='custom_fields'\n    )\n    name = ValidXMLCharField(_(u'name'), max_length=255, help_text=_(u'(max 255 characters)'))\n    section = models.IntegerField(\n        _(u'admin section'), choices=SECTIONS,\n        help_text=_(u'Select the section of the admin where the custom field should be displayed')\n    )\n    max_characters = models.IntegerField(\n        _(u'maximum characters'), blank=True, null=True,\n        help_text=_(u'Set the maximum amount of characters that the user is allowed to fill in. '\n                    u'Leave empty or fill in 0 if there is no character limit.')\n    )\n    help_text = ValidXMLTextField(\n        _(u'help text'), max_length=1000, blank=True,\n        help_text=_(u'The help text to be displayed with the field in the admin. Leave empty if '\n                    u'there is no need for a help text. (max 1000 characters)')\n    )\n    mandatory = models.BooleanField(_(u'mandatory'), default=False,\n                                    help_text=_(u'Indicate whether this field is mandatory or not'))\n    order = models.PositiveSmallIntegerField(\n        _(u'order'), help_text=_(u'The order of the fields as they will be displayed in the '\n                                 u'project editor. Must be a positive number, and the lowest '\n                                 u'number will be shown on top.')\n    )\n    type = ValidXMLCharField(\n        _(u'type'), max_length=20, choices=TYPES, default='text',\n        help_text=_(u'Select the type of custom field. Text will show a text area in the project '\n                    u'editor, and checkbox will show a checkbox.')\n    )\n", "path": "akvo/rsr/models/custom_field.py"}]}