More targeted import

pretix_matrix_inviter/forms.py

-from django import forms
+from django.forms import (
+    CharField,
+    CheckboxSelectMultiple,
+    MultipleChoiceField,
+    RegexField,
+)
 from django.utils.translation import ugettext_lazy as _
 from i18nfield.forms import I18nFormField, I18nTextInput
 from pretix.base.forms import SettingsForm
@@ -7,19 +12,17 @@ from .helpers import matrix_room_info_for_event
 
 
 class MatrixInviterForm(SettingsForm):
-    matrix_inviter_items = forms.MultipleChoiceField(
-        widget=forms.CheckboxSelectMultiple(
-            attrs={"class": "scrolling-multiple-choice"}
-        ),
+    matrix_inviter_items = MultipleChoiceField(
+        widget=CheckboxSelectMultiple(attrs={"class": "scrolling-multiple-choice"}),
         label=_("Ask Matrix ID for"),
         required=True,
         choices=[],
     )
-    matrix_inviter_authorization_token = forms.CharField(
+    matrix_inviter_authorization_token = CharField(
         label=_("Authorization token"),
         strip=True,
     )
-    matrix_inviter_matrix_server = forms.CharField(
+    matrix_inviter_matrix_server = CharField(
         label=_("Matrix server"),
         strip=True,
     )
@@ -54,7 +57,7 @@ class MatrixInviterForm(SettingsForm):
             else:
                 room_help_text = _('"{name}" (<code>{room_id}</code>)')
 
-        self.fields["matrix_inviter_matrix_room"] = forms.RegexField(
+        self.fields["matrix_inviter_matrix_room"] = RegexField(
             label=_("Matrix room"),
             regex="(!|#)[^:]+:.+",
             strip=True,