Removed unneeded string normalization in contrib.admin

With Python 2.7 and up, named parameter keys are not limited to
bytestrings any longer. This mainly reverts 3bd384a.

django/contrib/admin/helpers.py

@@ -30,7 +30,7 @@ class ActionForm(forms.Form):
 
 class AdminForm(object):
     def __init__(self, form, fieldsets, prepopulated_fields, readonly_fields=None, model_admin=None):
-        self.form, self.fieldsets = form, normalize_fieldsets(fieldsets)
+        self.form, self.fieldsets = form, fieldsets
         self.prepopulated_fields = [{
             'field': form[field_name],
             'dependencies': [form[f] for f in dependencies]
@@ -334,26 +334,3 @@ def __init__(self, form, inline_formsets):
                 self.extend(inline_formset.non_form_errors())
                 for errors_in_inline_form in inline_formset.errors:
                     self.extend(list(six.itervalues(errors_in_inline_form)))
-
-
-def normalize_fieldsets(fieldsets):
-    """
-    Make sure the keys in fieldset dictionaries are strings. Returns the
-    normalized data.
-    """
-    result = []
-    for name, options in fieldsets:
-        result.append((name, normalize_dictionary(options)))
-    return result
-
-
-def normalize_dictionary(data_dict):
-    """
-    Converts all the keys in "data_dict" to strings. The keys must be
-    convertible using str().
-    """
-    for key, value in data_dict.items():
-        if not isinstance(key, str):
-            del data_dict[key]
-            data_dict[str(key)] = value
-    return data_dict

django/contrib/admin/views/main.py

@@ -9,7 +9,7 @@
 from django.db.models.fields import FieldDoesNotExist
 from django.utils import six
 from django.utils.deprecation import RenameMethodsBase
-from django.utils.encoding import force_str, force_text
+from django.utils.encoding import force_text
 from django.utils.translation import ugettext, ugettext_lazy
 from django.utils.http import urlencode
 
@@ -142,14 +142,7 @@ def get_filters(self, request):
         lookup_params = self.get_filters_params()
         use_distinct = False
 
-        # Normalize the types of keys
         for key, value in lookup_params.items():
-            if not isinstance(key, str):
-                # 'key' will be used as a keyword argument later, so Python
-                # requires it to be a string.
-                del lookup_params[key]
-                lookup_params[force_str(key)] = value
-
             if not self.model_admin.lookup_allowed(key, value):
                 raise DisallowedModelAdminLookup("Filtering by %s not allowed" % key)