Add ability for specific backends to enable template escaping. Closes #441.

moto/ec2/responses/__init__.py

@@ -66,3 +66,7 @@ class EC2Response(
     def ec2_backend(self):
         from moto.ec2.models import ec2_backends
         return ec2_backends[self.region]
+
+    @property
+    def should_autoescape(self):
+        return True

moto/ec2/responses/tags.py

@@ -1,6 +1,5 @@
 from __future__ import unicode_literals
 
-from xml.sax.saxutils import escape
 from moto.core.responses import BaseResponse
 from moto.ec2.models import validate_resource_ids
 from moto.ec2.utils import sequence_from_querystring, tags_from_query_string, filters_from_querystring
@@ -26,8 +25,6 @@ class TagResponse(BaseResponse):
     def describe_tags(self):
         filters = filters_from_querystring(querystring_dict=self.querystring)
         tags = self.ec2_backend.describe_tags(filters=filters)
-        for tag in tags:
-            tag['value'] = escape(tag['value'])
         template = self.response_template(DESCRIBE_RESPONSE)
         return template.render(tags=tags)