diff --git a/sdks/python/apache_beam/typehints/typehints.py b/sdks/python/apache_beam/typehints/typehints.py
index 543641526f56..af9e1fef70b2 100644
--- a/sdks/python/apache_beam/typehints/typehints.py
+++ b/sdks/python/apache_beam/typehints/typehints.py
@@ -1127,7 +1127,6 @@ def coerce_to_kv_type(element_type, label=None):
         Union[tuple(t.tuple_types[1] for t in union_types)]]
   else:
     # TODO: Possibly handle other valid types.
-    print "element_type", element_type
     raise ValueError(
         "Input to %r must be compatible with KV[Any, Any]. "
         "Found %s." % (label, element_type))
diff --git a/sdks/python/build.gradle b/sdks/python/build.gradle
index 484adb3629e3..2c6637a53732 100644
--- a/sdks/python/build.gradle
+++ b/sdks/python/build.gradle
@@ -64,7 +64,7 @@ build.dependsOn buildPython
 task lint (dependsOn: 'setupTest') {
   doLast {
     exec {
-      commandLine 'tox', '-e', 'lint', '-c', 'tox.ini'
+      commandLine 'tox', '-e', '{py27,py3}-lint', '-c', 'tox.ini'
     }
   }
 }
@@ -74,7 +74,7 @@ check.dependsOn lint
 task testCython (dependsOn: ['setupTest', 'testPython', 'testGcp']) {
   doLast {
     exec {
-      commandLine 'tox', '-e', 'py27cython', '-c', 'tox.ini'
+      commandLine 'tox', '-e', 'py27-cython2', '-c', 'tox.ini'
     }
   }
 }
@@ -83,7 +83,7 @@ test.dependsOn testCython
 task testGcp (dependsOn: 'setupTest') {
   doLast {
     exec {
-      commandLine 'tox', '-e', 'py27gcp', '-c', 'tox.ini'
+      commandLine 'tox', '-e', 'py27-gcp', '-c', 'tox.ini'
     }
   }
 }
diff --git a/sdks/python/run_tox_cleanup.sh b/sdks/python/run_tox_cleanup.sh
new file mode 100755
index 000000000000..76b683cf588b
--- /dev/null
+++ b/sdks/python/run_tox_cleanup.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+#
+#    Licensed to the Apache Software Foundation (ASF) under one or more
+#    contributor license agreements.  See the NOTICE file distributed with
+#    this work for additional information regarding copyright ownership.
+#    The ASF licenses this file to You under the Apache License, Version 2.0
+#    (the "License"); you may not use this file except in compliance with
+#    the License.  You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS,
+#    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#    See the License for the specific language governing permissions and
+#    limitations under the License.
+#
+
+# This script is used to remove generated files in previous Tox runs so that
+# they are not picked up by tests.
+
+set -e
+
+for dir in apache_beam target/build; do
+    if [ -d "${dir}" ]; then
+        for ext in pyc c so; do
+            find ${dir} -type f -name "*.${ext}" -delete
+        done
+    fi
+done
diff --git a/sdks/python/setup.py b/sdks/python/setup.py
index 02c02f56c424..ffc4df784137 100644
--- a/sdks/python/setup.py
+++ b/sdks/python/setup.py
@@ -113,11 +113,8 @@ def get_version():
     'futures>=3.1.1,<4.0.0',
     ]
 
-REQUIRED_SETUP_PACKAGES = [
-    'nose>=1.0',
-    ]
-
 REQUIRED_TEST_PACKAGES = [
+    'nose>=1.3.7',
     'pyhamcrest>=1.9,<2.0',
     ]
 
@@ -177,6 +174,9 @@ def generate_common_urns():
         + '\n')
 generate_common_urns()
 
+python_requires = '>=2.7'
+if os.environ.get('BEAM_EXPERIMENTAL_PY3') is None:
+  python_requires += ',<3.0'
 
 setuptools.setup(
     name=PACKAGE_NAME,
@@ -202,9 +202,8 @@ def generate_common_urns():
         'apache_beam/utils/counters.py',
         'apache_beam/utils/windowed_value.py',
     ]),
-    setup_requires=REQUIRED_SETUP_PACKAGES,
     install_requires=REQUIRED_PACKAGES,
-    python_requires='>=2.7,<3.0',
+    python_requires=python_requires,
     test_suite='nose.collector',
     tests_require=REQUIRED_TEST_PACKAGES,
     extras_require={
diff --git a/sdks/python/tox.ini b/sdks/python/tox.ini
index 857e7b0e571f..add9bbfb2cc0 100644
--- a/sdks/python/tox.ini
+++ b/sdks/python/tox.ini
@@ -17,8 +17,7 @@
 
 [tox]
 # new environments will be excluded by default unless explicitly added to envlist.
-# TODO (after BEAM-3671) add lint_py3 back in.
-envlist = py27,py27gcp,py27cython,lint_py2,docs
+envlist = py27,py27-{gcp,cython2,lint},py3-lint,docs
 toxworkdir = {toxinidir}/target/.tox
 
 [pycodestyle]
@@ -26,128 +25,95 @@ toxworkdir = {toxinidir}/target/.tox
 # pylint does not check the number of blank lines.
 select = E3
 
+# Shared environment options.
+[testenv]
+# Set [] options for pip installation of apache-beam tarball.
+extras = test
+# Don't warn that these commands aren't installed.
+whitelist_externals =
+  find
+  time
+
 [testenv:py27]
-# autocomplete_test depends on nose when invoked directly.
-deps =
-  nose==1.3.7
-  grpcio-tools==1.3.5
-whitelist_externals=find
 commands =
   python --version
   pip --version
-  # Clean up all previous python generated files.
-  - find apache_beam -type f -name '*.pyc' -delete
-  pip install -e .[test]
+  {toxinidir}/run_tox_cleanup.sh
   python apache_beam/examples/complete/autocomplete_test.py
   python setup.py test
-passenv = TRAVIS*
+  {toxinidir}/run_tox_cleanup.sh
 
-[testenv:py27cython]
+# This environment will fail in Jenkins if named "py27-cython".
+[testenv:py27-cython2]
 # cython tests are only expected to work in linux (2.x and 3.x)
 # If we want to add other platforms in the future, it should be:
 # `platform = linux2|darwin|...`
 # See https://docs.python.org/2/library/sys.html#sys.platform for platform codes
 platform = linux2
-# autocomplete_test depends on nose when invoked directly.
 deps =
-  nose==1.3.7
-  grpcio-tools==1.3.5
-  cython==0.25.2
-whitelist_externals=
-  find
-  time
+  cython==0.26.1
 commands =
   python --version
   pip --version
-  # Clean up all previous python generated files.
-  - find apache_beam -type f -name '*.pyc' -delete
-  # Clean up all previous cython generated files.
-  - find apache_beam -type f -name '*.c' -delete
-  - find apache_beam -type f -name '*.so' -delete
-  - find target/build -type f -name '*.c' -delete
-  - find target/build -type f -name '*.so' -delete
-  time pip install -e .[test]
+  {toxinidir}/run_tox_cleanup.sh
   python apache_beam/examples/complete/autocomplete_test.py
   python setup.py test
-  # Clean up all cython generated files. Ignore if deletion fails.
-  - find apache_beam -type f -name '*.c' -delete
-  - find apache_beam -type f -name '*.so' -delete
-  - find target/build -type f -name '*.c' -delete
-  - find target/build -type f -name '*.so' -delete
-passenv = TRAVIS*
+  {toxinidir}/run_tox_cleanup.sh
 
-[testenv:py27gcp]
-# autocomplete_test depends on nose when invoked directly.
-deps =
-  nose==1.3.7
-whitelist_externals=find
+[testenv:py27-gcp]
+extras = test,gcp
 commands =
   python --version
   pip --version
-  pip install -e .[test,gcp]
-  # Clean up all previous python generated files.
-  - find apache_beam -type f -name '*.pyc' -delete
+  {toxinidir}/run_tox_cleanup.sh
   python apache_beam/examples/complete/autocomplete_test.py
   python setup.py test
-passenv = TRAVIS*
+  {toxinidir}/run_tox_cleanup.sh
 
-[testenv:lint_py2]
-deps=
-  nose==1.3.7
+[testenv:py27-lint]
+deps =
   pycodestyle==2.3.1
   pylint==1.7.2
   future==0.16.0
   isort==4.2.15
   flake8==3.5.0
-whitelist_externals=time
 commands =
   python --version
   pip --version
-  time pip install -e .[test]
   time {toxinidir}/run_pylint.sh
-passenv = TRAVIS*
 
-[testenv:lint_py3]
-deps=
-  nose==1.3.7
+[testenv:py3-lint]
+deps =
   pycodestyle==2.3.1
   pylint==1.7.2
   future==0.16.0
   isort==4.2.15
   flake8==3.5.0
-whitelist_externals=time
+setenv =
+    BEAM_EXPERIMENTAL_PY3=1
 commands =
-  time pip install -e .[test]
+  python --version
+  pip --version
   time {toxinidir}/run_mini_py3lint.sh
-passenv = TRAVIS*
-
 
 [testenv:docs]
-deps=
-  nose==1.3.7
-  grpcio-tools==1.3.5
+extras = test,gcp,docs
+deps =
   Sphinx==1.6.5
   sphinx_rtd_theme==0.2.4
-whitelist_externals=time
 commands =
   python --version
   pip --version
-  time pip install -e .[test,gcp,docs]
   time {toxinidir}/generate_pydoc.sh
-passenv = TRAVIS*
 
 [testenv:cover]
 # This is not included in envlist which is defined in [tox].
 deps =
   coverage==4.4.1
-  nose==1.3.7
-whitelist_externals=find
 commands =
   python --version
   pip --version
-  pip install -e .[test,gcp]
-  # Clean up all previous python generated files.
-  - find apache_beam -type f -name '*.pyc' -delete
+  {toxinidir}/run_tox_cleanup.sh
   # Clean up previously collected data.
   coverage erase
   coverage run setup.py test
@@ -155,4 +121,3 @@ commands =
   coverage report --skip-covered
   # Generate report in xml format
   coverage xml
-passenv = TRAVIS*