diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index 377e8c4a9..dd4572911 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -14,7 +14,8 @@ jobs:
     strategy:
       max-parallel: 1
       matrix:
-        python-version: [3.7, 3.8]
+        # TODO: unlock parallel testing by using more API keys
+        python-version: [3.6]
 
     steps:
 
@@ -57,7 +58,7 @@ jobs:
         mypy -p labelbox --pretty --show-error-codes
     - name: Install package and test dependencies
       run: |
-        pip install tox==3.18.1 tox-gh-actions==1.3.0
+        pip install tox==3.18.1 tox-gh-actions==1.3.0 pytest-parallel==0.1.0
 
     # TODO: replace tox.ini with what the Makefile does
     # to make sure local testing is
@@ -72,4 +73,4 @@ jobs:
         # randall+staging-python@labelbox.com
         LABELBOX_TEST_API_KEY_STAGING: ${{ secrets.STAGING_LABELBOX_API_KEY }}
       run: |
-        tox -- -svv
+        pytest --workers 2 -svv
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 31dc844fa..97f7c6f11 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## Version 2.4.7 (2020-09-10)
+### Added
+* `Ontology` schema for interacting with ontologies and their schema nodes
+
 ## Version 2.4.6 (2020-09-03)
 ### Fix
 * fix failing `create_metadata` calls
diff --git a/Dockerfile b/Dockerfile
index d825f76ab..91c97e336 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM python:3
+FROM python:3.6
 
 COPY . /usr/src/labelbox
 WORKDIR /usr/src/labelbox
diff --git a/labelbox/schema/project.py b/labelbox/schema/project.py
index c83b2db96..3d387b7f8 100644
--- a/labelbox/schema/project.py
+++ b/labelbox/schema/project.py
@@ -15,6 +15,12 @@
 from labelbox.orm.model import Entity, Field, Relationship
 from labelbox.pagination import PaginatedCollection
 
+try:
+    datetime.fromisoformat  # type: ignore[attr-defined]
+except AttributeError:
+    from backports.datetime_fromisoformat import MonkeyPatch
+    MonkeyPatch.patch_fromisoformat()
+
 logger = logging.getLogger(__name__)
 
 
diff --git a/setup.py b/setup.py
index a5f4cbb0c..8d0f0a610 100644
--- a/setup.py
+++ b/setup.py
@@ -5,7 +5,7 @@
 
 setuptools.setup(
     name="labelbox",
-    version="2.4.6",
+    version="2.4.7",
     author="Labelbox",
     author_email="engineering@labelbox.com",
     description="Labelbox Python API",
@@ -15,6 +15,8 @@
     packages=setuptools.find_packages(),
     install_requires=[
         "backoff==1.10.0",
+        "backports-datetime-fromisoformat",
+        "dataclasses",
         "ndjson==0.3.1",
         "requests>=2.22.0",
         "google-api-core>=1.22.1",
@@ -23,9 +25,10 @@
         'Development Status :: 3 - Alpha',
         'License :: OSI Approved :: Apache Software License',
         'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
     ],
-    python_requires='>=3.7',
+    python_requires='>=3.6',
     keywords=["labelbox"],
 )
diff --git a/tox.ini b/tox.ini
index 709763dea..3297034c3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,9 +1,10 @@
 # content of: tox.ini , put in same dir as setup.py
 [tox]
-envlist = py37, py38
+envlist = py36, py37, py38
 
 [gh-actions]
 python =
+    3.6: py36
     3.7: py37
     3.8: py38