diff --git a/tests/test_query_version.py b/tests/test_query_version.py
index 78a58e60626f5f2af903fab0d48dd2c863b1d020..223773d10822927a143f82fece47afb0da446549 100644
--- a/tests/test_query_version.py
+++ b/tests/test_query_version.py
@@ -58,10 +58,19 @@ TEST_REC_1 = db.Record(
 
 TEST_PROP_TEXT_2 = db.Property("TestPropertyText2", datatype=db.TEXT)
 TEST_BACKREF_RT = db.RecordType("TestBackRefRecordType")
-TEST_BACKREF_0 = db.Record("TestBackRef0", description="bref0").add_parent(TEST_BACKREF_RT).add_property(TEST_RT_1, "TestRecord1").add_property(TEST_PROP_TEXT_2, "val0")
-TEST_BACKREF_1 = db.Record("TestBackRef1", description="bref1").add_parent(TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val1")
-TEST_BACKREF_2 = db.Record("TestBackRef2", description="bref2").add_parent(TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val2")
-TEST_BACKREF_3 = db.Record("TestBackRef3", description="bref3").add_parent(TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val3")
+TEST_BACKREF_0 = db.Record(
+    "TestBackRef0",
+    description="bref0").add_parent(TEST_BACKREF_RT).add_property(
+        TEST_RT_1,
+        "TestRecord1").add_property(
+            TEST_PROP_TEXT_2,
+    "val0")
+TEST_BACKREF_1 = db.Record("TestBackRef1", description="bref1").add_parent(
+    TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val1")
+TEST_BACKREF_2 = db.Record("TestBackRef2", description="bref2").add_parent(
+    TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val2")
+TEST_BACKREF_3 = db.Record("TestBackRef3", description="bref3").add_parent(
+    TEST_BACKREF_RT).add_property(TEST_PROP_TEXT_2, "val3")
 
 
 def teardown_module():
@@ -73,9 +82,11 @@ def setup_module():
                       TEST_PROP_INTEGER, TEST_PROP_DATETIME, TEST_PROP_DATE,
                       TEST_REF_RT, TEST_REF_1, TEST_REF_2, TEST_REF_3,
                       TEST_BACKREF_RT, TEST_BACKREF_0, TEST_PROP_TEXT_2,
-                     ]).insert()
+                      ]).insert()
     CONTAINER.append(TEST_BACKREF_1)
-    TEST_BACKREF_1.add_property(TEST_RT_1, str(TEST_REC_1.id)+"@HEAD").insert()
+    TEST_BACKREF_1.add_property(
+        TEST_RT_1, str(
+            TEST_REC_1.id) + "@HEAD").insert()
 
     # update test_rec_1 two times
     TEST_REC_1.description = "v2"
@@ -88,7 +99,9 @@ def setup_module():
     TEST_REC_1.update()
 
     CONTAINER.append(TEST_BACKREF_2)
-    TEST_BACKREF_2.add_property(TEST_RT_1, str(TEST_REC_1.id)+"@HEAD").insert()
+    TEST_BACKREF_2.add_property(
+        TEST_RT_1, str(
+            TEST_REC_1.id) + "@HEAD").insert()
 
     TEST_REC_1.description = "v3"
     TEST_REC_1.get_property(TEST_PROP_TEXT).value = "val3"
@@ -100,7 +113,9 @@ def setup_module():
     TEST_REC_1.update()
 
     CONTAINER.append(TEST_BACKREF_3)
-    TEST_BACKREF_3.add_property(TEST_RT_1, str(TEST_REC_1.id)+"@HEAD").insert()
+    TEST_BACKREF_3.add_property(
+        TEST_RT_1, str(
+            TEST_REC_1.id) + "@HEAD").insert()
 
 
 def test_normal_find_record():
@@ -186,14 +201,16 @@ def test_normal_find_record():
 
     result = query("FIND RECORD TestRefRecordType WITH NOT TestPropertyText")
     assert len(result) == 3
-    assert set(["ref1", "ref2", "ref3"]) == set([r.description for r in result])
+    assert set(["ref1", "ref2", "ref3"]) == set(
+        [r.description for r in result])
 
     result = query("FIND RECORD TestRecord1 WITH NOT TestPropertyText")
     assert len(result) == 0
 
     result = query("FIND RECORD WITH NOT TestPropertyText")
     assert len(result) == 7
-    assert set(["ref1", "ref2", "ref3", "bref0", "bref1", "bref2", "bref3",]) == set([r.description for r in result])
+    assert set(["ref1", "ref2", "ref3", "bref0", "bref1", "bref2",
+                "bref3", ]) == set([r.description for r in result])
 
     result = query("FIND RECORD WHICH IS REFERENCED BY TestBackRefRecordType")
     assert len(result) == 1
@@ -203,12 +220,14 @@ def test_normal_find_record():
     assert len(result) == 1
     assert result[0].description == "v3"
 
-    result = query("FIND RECORD WHICH IS REFERENCED BY TestBackRefRecordType WITH TestPropertyText2=val0")
+    result = query(
+        "FIND RECORD WHICH IS REFERENCED BY TestBackRefRecordType WITH TestPropertyText2=val0")
     assert len(result) == 1
     assert result[0].description == "v3"
 
 
-@pytest.mark.xfail(reason="Find queries which respect the version of the references are not supported yet and return false positives.")
+@pytest.mark.xfail(
+    reason="Find queries which respect the version of the references are not supported yet and return false positives.")
 def test_normal_find_with_versioned_reference():
     # current version is not referenced
     result = query("FIND RECORD WHICH IS REFERENCED BY TestBackRef1")
@@ -416,71 +435,88 @@ def test_find_any_version_of_record_with_simple_reference_filter():
 
 
 def test_find_any_version_of_record_with_conjunction_filter():
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType AND TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType AND TestPropertyText")
     assert len(result) == 3
     assert set(["v3", "v2", "v1"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText")
     assert len(result) == 1
     assert result[0].description == "v3"
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText = val3")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText = val3")
     assert len(result) == 1
     assert result[0].description == "v3"
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 AND TestPropertyText = val2")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 AND TestPropertyText = val2")
     assert len(result) == 1
     assert result[0].description == "v2"
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText = val2")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 AND TestPropertyText = val2")
     assert len(result) == 0
 
 
 def test_find_any_version_of_record_with_disjunction_filter():
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType OR TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType OR TestPropertyText")
     assert len(result) == 3
     assert set(["v3", "v2", "v1"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 OR TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 OR TestPropertyText")
     assert len(result) == 3
     assert set(["v3", "v2", "v1"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText")
     assert len(result) == 3
     assert set(["v3", "v2", "v1"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 OR TestPropertyText = val3")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef3 OR TestPropertyText = val3")
     assert len(result) == 1
     assert result[0].description == "v3"
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val2")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val2")
     assert len(result) == 1
     assert result[0].description == "v2"
 
-    result = query("FIND ANY VERSION OF TestRecord1  WITH TestRefRecordType = TestRef2 OR TestPropertyText = val2")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1  WITH TestRefRecordType = TestRef2 OR TestPropertyText = val2")
     assert len(result) == 1
     assert result[0].description == "v2"
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val3")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val3")
     assert len(result) == 2
     assert set(["v3", "v2"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val3 OR TestPropertyInteger = 200")
+    result = query(
+        "FIND ANY VERSION OF RECORD WITH TestRefRecordType = TestRef2 OR TestPropertyText = val3 OR TestPropertyInteger = 200")
     assert len(result) == 2
     assert set(["v3", "v2"]) == set([r.description for r in result])
 
 
 def test_find_any_version_of_record_with_negation_filter():
-    result = query("FIND ANY VERSION OF RECORD WHICH DOES NOT HAVE A TestPropertyText")
+    result = query(
+        "FIND ANY VERSION OF RECORD WHICH DOES NOT HAVE A TestPropertyText")
     assert len(result) == 7
-    assert set(["ref1", "ref2", "ref3", "bref0", "bref1", "bref2", "bref3",]) == set([r.description for r in result])
+    assert set(["ref1", "ref2", "ref3", "bref0", "bref1", "bref2",
+                "bref3", ]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD WHICH DOES NOT HAVE A TestPropertyText=val2")
+    result = query(
+        "FIND ANY VERSION OF RECORD WHICH DOES NOT HAVE A TestPropertyText=val2")
     assert len(result) == 9
     assert set(["ref1", "ref2", "ref3", "bref0", "bref1", "bref2", "bref3",
                 "v1", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD TestRecord1 WHICH DOES NOT HAVE A TestPropertyText=val2")
+    result = query(
+        "FIND ANY VERSION OF RECORD TestRecord1 WHICH DOES NOT HAVE A TestPropertyText=val2")
     assert len(result) == 2
     assert set(["v1", "v3"]) == set([r.description for r in result])
 
@@ -492,48 +528,60 @@ def test_find_any_version_of_record_with_complex_filter():
 
 
 def test_find_any_version_of_record_with_backref_filter():
-    result = query("FIND ANY VERSION OF RECORD WHICH IS REFERENCED BY TestBackRefRecordType")
+    result = query(
+        "FIND ANY VERSION OF RECORD WHICH IS REFERENCED BY TestBackRefRecordType")
     assert len(result) == 3
     assert set(["v1", "v2", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF RECORD TestRecord1 WHICH IS REFERENCED BY TestBackRefRecordType")
+    result = query(
+        "FIND ANY VERSION OF RECORD TestRecord1 WHICH IS REFERENCED BY TestBackRefRecordType")
     assert len(result) == 3
     assert set(["v1", "v2", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRefRecordType")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRefRecordType")
     assert len(result) == 3
     assert set(["v1", "v2", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef0")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef0")
     assert len(result) == 3
     assert set(["v1", "v2", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef0")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef0")
     assert len(result) == 3
     assert set(["v1", "v2", "v3"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef1")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef1")
     assert len(result) == 1
     assert set(["v1"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef2")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef2")
     assert len(result) == 1
     assert set(["v2"]) == set([r.description for r in result])
 
-    result = query("FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef3")
+    result = query(
+        "FIND ANY VERSION OF TestRecord1 WHICH IS REFERENCED BY TestBackRef3")
     assert len(result) == 1
     assert set(["v3"]) == set([r.description for r in result])
 
 
-@pytest.mark.xfail(reason="versioned queries with subqueries are not supported yet")
+@pytest.mark.xfail(
+    reason="versioned queries with subqueries are not supported yet")
 def test_find_any_version_of_record_with_backref_and_subquery():
-    assert query("FIND ANY VERSION OF RECORD WHICH IS REFERENCED BY TestBackRefRecordType WITH name = TestBackRef0")
+    assert query(
+        "FIND ANY VERSION OF RECORD WHICH IS REFERENCED BY TestBackRefRecordType WITH name = TestBackRef0")
     assert len(result) == 1
     assert set(["v3"]) == set([r.description for r in result])
 
 
-@pytest.mark.xfail(reason="versioned queries with subqueries are not supported yet")
+@pytest.mark.xfail(
+    reason="versioned queries with subqueries are not supported yet")
 def test_find_any_version_of_record_with_ref_and_subquery():
-    assert query("FIND ANY VERSION OF RECORD WHICH REFERENCES TestRefRecordType WITH name = TestRef2")
+    assert query(
+        "FIND ANY VERSION OF RECORD WHICH REFERENCES TestRefRecordType WITH name = TestRef2")
     assert len(result) == 1
     assert set(["v3"]) == set([r.description for r in result])