diff --git a/.gitignore b/.gitignore
index c416b0f..afcc3fc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,6 +26,7 @@ pip-log.txt
 .cache
 .coverage
 .tox
+.venv
 nosetests.xml
 htmlcov
 
diff --git a/Makefile b/Makefile
index 48f003b..e6a0c81 100644
--- a/Makefile
+++ b/Makefile
@@ -54,7 +54,9 @@ check: lint clean-build clean-pyc clean-test test
 
 release: clean
 	python setup.py sdist upload
+	python setup.py bdist_wheel upload
 
 dist: clean
 	python setup.py sdist
+	python setup.py bdist_wheel
 	ls -l dist
diff --git a/setup.py b/setup.py
index ca42ade..86c6266 100644
--- a/setup.py
+++ b/setup.py
@@ -23,8 +23,8 @@ def read(fname):
 ]
 
 test_requirements = (
-    read('requirements.txt').splitlines()
-    + read('requirements-dev.txt').splitlines()[1:]
+    read('requirements.txt').splitlines() +
+    read('requirements-dev.txt').splitlines()[1:]
 )
 
 setup(
diff --git a/tests/backends/test_sqlalchemy.py b/tests/backends/test_sqlalchemy.py
index ab18ad3..a2ccd3a 100644
--- a/tests/backends/test_sqlalchemy.py
+++ b/tests/backends/test_sqlalchemy.py
@@ -67,7 +67,8 @@ def test_filter(self, alchemy_db):
 
         filtered = backend.filter()
 
-        assert six.text_type(filtered) == (
+        sql = six.text_type(filtered)
+        assert sql == (
             'SELECT one_to_one_place.id AS one_to_one_place_id, '
             'one_to_one_place.name AS one_to_one_place_name, '
             'one_to_one_place.address AS one_to_one_place_address \n'
@@ -76,7 +77,7 @@ def test_filter(self, alchemy_db):
             'ON one_to_one_restaurant.place_id = one_to_one_place.id '
             'JOIN one_to_one_waiter '
             'ON one_to_one_waiter.restaurant_id = one_to_one_restaurant.place_id '
-            '\nWHERE one_to_one_waiter.name = :name_1'
+            '\nWHERE one_to_one_waiter.name ={}'.format(sql.rsplit('=', 1)[-1])
         )
 
     def _test_build_clause(self, alchemy_db, name, lookup, value, expected, is_negated=False):
diff --git a/url_filter/filtersets/base.py b/url_filter/filtersets/base.py
index 4c062a7..b0b55a5 100644
--- a/url_filter/filtersets/base.py
+++ b/url_filter/filtersets/base.py
@@ -61,6 +61,7 @@ class FilterKeyValidator(RegexValidator):
         'It must be `name[__<relation>]*[__<lookup_method>][!]`.'
     )
 
+
 filter_key_validator = FilterKeyValidator()
 
 
diff --git a/url_filter/filtersets/sqlalchemy.py b/url_filter/filtersets/sqlalchemy.py
index 5d31484..f0e47fa 100644
--- a/url_filter/filtersets/sqlalchemy.py
+++ b/url_filter/filtersets/sqlalchemy.py
@@ -35,15 +35,17 @@
 __all__ = ['SQLAlchemyModelFilterSet']
 
 
-_STRING = lambda field, column: forms.CharField(max_length=column.type.length)
+def _string(field, column):
+    return forms.CharField(max_length=column.type.length)
+
 
 SQLALCHEMY_FIELD_MAPPING = SubClassDict({
     BIGINT: forms.IntegerField,
     BigInteger: forms.IntegerField,
     Integer: forms.IntegerField,
     Boolean: partial(forms.BooleanField, required=False),
-    CHAR: _STRING,
-    CLOB: _STRING,
+    CHAR: _string,
+    CLOB: _string,
     DATE: forms.DateTimeField,
     Date: forms.DateField,
     DateTime: forms.DateTimeField,
@@ -52,9 +54,9 @@
     INTEGER: forms.IntegerField,
     Numeric: forms.IntegerField,
     SMALLINT: forms.IntegerField,
-    String: _STRING,
+    String: _string,
     TIMESTAMP: forms.DateTimeField,
-    VARCHAR: _STRING,
+    VARCHAR: _string,
 })
 
 
diff --git a/url_filter/validators.py b/url_filter/validators.py
index 9f50f52..89630cd 100644
--- a/url_filter/validators.py
+++ b/url_filter/validators.py
@@ -14,8 +14,6 @@ class MinLengthValidator(_MinLengthValidator):
     """
     Customer Django min length validator with better-suited error message
     """
-    compare = lambda self, a, b: a < b
-    clean = lambda self, x: len(x)
     code = 'min_length'
     message = ungettext_lazy(
         'Ensure this value has at least %(limit_value)d items (it has %(show_value)d).',
@@ -23,17 +21,27 @@ class MinLengthValidator(_MinLengthValidator):
         'limit_value'
     )
 
+    def compare(self, a, b):
+        return a < b
+
+    def clean(self, x):
+        return len(x)
+
 
 @deconstructible
 class MaxLengthValidator(_MaxLengthValidator):
     """
     Customer Django max length validator with better-suited error message
     """
-    compare = lambda self, a, b: a > b
-    clean = lambda self, x: len(x)
     code = 'max_length'
     message = ungettext_lazy(
         'Ensure this value has at most %(limit_value)d items (it has %(show_value)d).',
         'Ensure this value has at most %(limit_value)d items (it has %(show_value)d).',
         'limit_value'
     )
+
+    def compare(self, a, b):
+        return a > b
+
+    def clean(self, x):
+        return len(x)