diff --git a/.travis.yml b/.travis.yml
index 260054a..4d45da9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,7 @@ language: python
 sudo: false
 matrix:
   include:
+  - python: 2.7
   - python: 3.4
   - python: 3.5
   - python: 3.6
diff --git a/openapi_core/__init__.py b/openapi_core/__init__.py
index e8e7031..90f9d02 100644
--- a/openapi_core/__init__.py
+++ b/openapi_core/__init__.py
@@ -1,8 +1,4 @@
 # -*- coding: utf-8 -*-
-
-"""Python 2.7 backward compatibility"""
-import openapi_core._python27_patch
-
 """OpenAPI core module"""
 from openapi_core.shortcuts import (
     create_spec, validate_parameters, validate_body, validate_data,
diff --git a/openapi_core/_python27_patch.py b/openapi_core/compat.py
similarity index 71%
rename from openapi_core/_python27_patch.py
rename to openapi_core/compat.py
index 81fc3df..53eeadf 100644
--- a/openapi_core/_python27_patch.py
+++ b/openapi_core/compat.py
@@ -1,14 +1,12 @@
-import functools
+"""OpenAPI core python 2.7 compatibility module"""
 try:
     from functools import lru_cache
-
 except ImportError:
     from backports.functools_lru_cache import lru_cache
-    functools.lru_cache = lru_cache
 
 try:
     from functools import partialmethod
-
 except ImportError:
     from backports.functools_partialmethod import partialmethod
-    functools.partialmethod = partialmethod
+
+__all__ = ['lru_cache', 'partialmethod']
diff --git a/openapi_core/schema/components/factories.py b/openapi_core/schema/components/factories.py
index 8ee7ceb..d784d44 100644
--- a/openapi_core/schema/components/factories.py
+++ b/openapi_core/schema/components/factories.py
@@ -1,5 +1,4 @@
-from functools import lru_cache
-
+from openapi_core.compat import lru_cache
 from openapi_core.schema.components.models import Components
 from openapi_core.schema.schemas.generators import SchemasGenerator
 
diff --git a/openapi_core/schema/operations/generators.py b/openapi_core/schema/operations/generators.py
index 0f225cc..8afeb9b 100644
--- a/openapi_core/schema/operations/generators.py
+++ b/openapi_core/schema/operations/generators.py
@@ -1,10 +1,9 @@
 # -*- coding: utf-8 -*-
 """OpenAPI core operations models module"""
-from functools import lru_cache
-
 from six import iteritems
 from openapi_spec_validator.validators import PathItemValidator
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.operations.models import Operation
 from openapi_core.schema.parameters.generators import ParametersGenerator
 from openapi_core.schema.request_bodies.factories import RequestBodyFactory
diff --git a/openapi_core/schema/parameters/generators.py b/openapi_core/schema/parameters/generators.py
index bc7f0da..0f5d78e 100644
--- a/openapi_core/schema/parameters/generators.py
+++ b/openapi_core/schema/parameters/generators.py
@@ -1,8 +1,7 @@
 """OpenAPI core parameters generators module"""
-from functools import lru_cache
-
 from six import iteritems
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.parameters.factories import ParameterFactory
 
 
diff --git a/openapi_core/schema/paths/generators.py b/openapi_core/schema/paths/generators.py
index 71c83a2..9289124 100644
--- a/openapi_core/schema/paths/generators.py
+++ b/openapi_core/schema/paths/generators.py
@@ -1,8 +1,7 @@
 """OpenAPI core paths generators module"""
-from functools import lru_cache
-
 from six import iteritems
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.operations.generators import OperationsGenerator
 from openapi_core.schema.paths.models import Path
 
diff --git a/openapi_core/schema/request_bodies/factories.py b/openapi_core/schema/request_bodies/factories.py
index 63d387e..ba659a3 100644
--- a/openapi_core/schema/request_bodies/factories.py
+++ b/openapi_core/schema/request_bodies/factories.py
@@ -1,6 +1,5 @@
 """OpenAPI core request bodies factories module"""
-from functools import lru_cache
-
+from openapi_core.compat import lru_cache
 from openapi_core.schema.media_types.generators import MediaTypeGenerator
 from openapi_core.schema.request_bodies.models import RequestBody
 
diff --git a/openapi_core/schema/responses/generators.py b/openapi_core/schema/responses/generators.py
index b6a410f..5e99ab2 100644
--- a/openapi_core/schema/responses/generators.py
+++ b/openapi_core/schema/responses/generators.py
@@ -1,8 +1,7 @@
 """OpenAPI core responses generators module"""
-from functools import lru_cache
-
 from six import iteritems
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.media_types.generators import MediaTypeGenerator
 from openapi_core.schema.parameters.generators import ParametersGenerator
 from openapi_core.schema.responses.models import Response
diff --git a/openapi_core/schema/schemas/factories.py b/openapi_core/schema/schemas/factories.py
index adad164..4d1f07f 100644
--- a/openapi_core/schema/schemas/factories.py
+++ b/openapi_core/schema/schemas/factories.py
@@ -1,7 +1,7 @@
 """OpenAPI core schemas factories module"""
 import logging
-from functools import lru_cache
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.properties.generators import PropertiesGenerator
 from openapi_core.schema.schemas.models import Schema
 
diff --git a/openapi_core/schema/servers/generators.py b/openapi_core/schema/servers/generators.py
index 86b079a..d05b589 100644
--- a/openapi_core/schema/servers/generators.py
+++ b/openapi_core/schema/servers/generators.py
@@ -1,8 +1,7 @@
 """OpenAPI core servers generators module"""
-from functools import lru_cache
-
 from six import iteritems
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.servers.models import Server, ServerVariable
 
 
diff --git a/openapi_core/schema/specs/factories.py b/openapi_core/schema/specs/factories.py
index 06868f6..16f736d 100644
--- a/openapi_core/schema/specs/factories.py
+++ b/openapi_core/schema/specs/factories.py
@@ -1,9 +1,9 @@
 # -*- coding: utf-8 -*-
 """OpenAPI core specs factories module"""
-from functools import lru_cache
 
 from openapi_spec_validator import openapi_v3_spec_validator
 
+from openapi_core.compat import lru_cache
 from openapi_core.schema.components.factories import ComponentsFactory
 from openapi_core.schema.infos.factories import InfoFactory
 from openapi_core.schema.paths.generators import PathsGenerator
diff --git a/openapi_core/schema/specs/models.py b/openapi_core/schema/specs/models.py
index 79a27e8..629c24e 100644
--- a/openapi_core/schema/specs/models.py
+++ b/openapi_core/schema/specs/models.py
@@ -1,8 +1,8 @@
 # -*- coding: utf-8 -*-
 """OpenAPI core specs models module"""
 import logging
-from functools import partialmethod
 
+from openapi_core.compat import partialmethod
 from openapi_core.schema.operations.exceptions import InvalidOperation
 from openapi_core.schema.servers.exceptions import InvalidServer
 
diff --git a/openapi_core/validation/util.py b/openapi_core/validation/util.py
index 62a3cb4..ace45e2 100644
--- a/openapi_core/validation/util.py
+++ b/openapi_core/validation/util.py
@@ -1,9 +1,5 @@
 """OpenAPI core validation util module"""
-try:
-    from urllib.parse import urlparse
-
-except ImportError:
-    from urlparse import urlparse
+from six.moves.urllib.parse import urlparse
 
 
 def is_absolute(url):
diff --git a/requirements_2.7.txt b/requirements_2.7.txt
index 624bfea..19ba7bb 100644
--- a/requirements_2.7.txt
+++ b/requirements_2.7.txt
@@ -1,5 +1,6 @@
 openapi-spec-validator
 six
+lazy-object-proxy
 backports.functools-lru-cache
 backports.functools-partialmethod
 enum34
diff --git a/setup.py b/setup.py
index 3bb9b26..8813608 100644
--- a/setup.py
+++ b/setup.py
@@ -25,6 +25,11 @@ def get_metadata(init_file):
     return dict(re.findall("__([a-z]+)__ = '([^']+)'", init_file))
 
 
+def install_requires():
+    py27 = '_2.7' if sys.version_info < (3,) else ''
+    return read_requirements('requirements{}.txt'.format(py27))
+
+
 class PyTest(TestCommand):
 
     """Command to run unit tests after in-place build."""
@@ -53,8 +58,6 @@ init_path = os.path.join('openapi_core', '__init__.py')
 init_py = read_file(init_path)
 metadata = get_metadata(init_py)
 
-py27 = '_2.7' if sys.version_info < (3,) else ''
-
 
 setup(
     name='openapi-core',
@@ -70,13 +73,13 @@ setup(
         'Intended Audience :: Developers',
         "Topic :: Software Development :: Libraries :: Python Modules",
         "Operating System :: OS Independent",
-        'Programming Language :: Python :: 3.4',
+        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Topic :: Software Development :: Libraries',
     ],
-    install_requires=read_requirements('requirements{}.txt'.format(py27)),
+    install_requires=install_requires(),
     tests_require=read_requirements('requirements_dev.txt'),
     extras_require={
         'flask':  ["werkzeug"],
diff --git a/tests/unit/validation/test_util.py b/tests/unit/validation/test_util.py
new file mode 100644
index 0000000..8cf353c
--- /dev/null
+++ b/tests/unit/validation/test_util.py
@@ -0,0 +1,18 @@
+from openapi_core.validation.util import path_qs
+
+
+class TestPathQs(object):
+
+    def test_path(self):
+        url = 'https://test.com:1234/path'
+
+        result = path_qs(url)
+
+        assert result == '/path'
+
+    def test_query(self):
+        url = 'https://test.com:1234/path?query=1'
+
+        result = path_qs(url)
+
+        assert result == '/path?query=1'