PEP8 clean-up

jsignature/fields.py

@@ -4,10 +4,11 @@
 """
 import json
 from django.db import models
-from django.core import validators
 from django.core.exceptions import ValidationError
-from .forms import (JSignatureField as JSignatureFormField,
-JSIGNATURE_EMPTY_VALUES)
+from .forms import (
+    JSignatureField as JSignatureFormField,
+    JSIGNATURE_EMPTY_VALUES)
+
 
 class JSignatureField(models.Field):
     """