add compatibility with django-select2 < 5

bijoe/forms.py

@@ -19,7 +19,10 @@ import datetime
 from django import forms
 from django.utils.translation import ugettext as _
 
-from django_select2.forms import Select2MultipleWidget
+try:
+    from django_select2.forms import Select2MultipleWidget
+except ImportError:
+    from django_select2.widgets import Select2MultipleWidget
 
 
 class DateRangeWidget(forms.MultiWidget):