Expression filter hack

hack.patch

diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py
index 4306193..bf965c1 100644
--- a/django/db/models/expressions.py
+++ b/django/db/models/expressions.py
@@ -340,11 +340,27 @@ def reverse_ordering(self):
         return self
 
 
+class ExpressionFilter(object):
+    def __init__(self, expression, value, lookup):
+        self.expression = expression
+        self.value = value
+        lookup = expression.get_lookup(lookup)
+        self.lookup = lookup
+
+    def resolve(self, query):
+        lhs = self.expression.resolve_expression(query)
+        return self.lookup(lhs, self.value)
+
+
 class Expression(BaseExpression, Combinable):
     """
     An expression that can be combined with other expressions.
     """
-    pass
+    def __eq__(self, other):
+        return ExpressionFilter(self, other, 'exact')
+
+    def __lt__(self, other):
+        return ExpressionFilter(self, other, 'lt')
 
 
 class CombinedExpression(Expression):
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index 88093d4..4c067df 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -16,7 +16,7 @@
 from django.db import DEFAULT_DB_ALIAS, connections
 from django.db.models.aggregates import Count
 from django.db.models.constants import LOOKUP_SEP
-from django.db.models.expressions import Col, Ref
+from django.db.models.expressions import Col, Ref, ExpressionFilter
 from django.db.models.fields.related_lookups import MultiColSource
 from django.db.models.query_utils import Q, PathInfo, refs_expression
 from django.db.models.sql.constants import (
@@ -1142,6 +1142,11 @@ def build_filter(self, filter_expr, branch_negated=False, current_negated=False,
         """
         if isinstance(filter_expr, dict):
             raise FieldError("Cannot parse keyword query as dict")
+        if isinstance(filter_expr, ExpressionFilter):
+            clause = self.where_class()
+            condition = filter_expr.resolve(self)
+            clause.add(condition, AND)
+            return clause, []
         arg, value = filter_expr
         if not arg:
             raise FieldError("Cannot parse keyword query %r" % arg)