DeprecationWarning: BaseException.message has been deprecated as of Python 2.6

When running the Heat unit tests, most of the output is deprecation warnings from line 526 of openstack/common/db/sqlalchemy/session.py:

$ tox -e py27
py27 develop-inst-nodeps: /home/jason/github/heat
py27 runtests: commands[0] | python setup.py testr --slowest --testr-args=
[pbr] Excluding argparse: Python 2.6 only dependency
running testr
running=
PYTHON=$(echo ${PYTHON:-python} | sed 's/--source heat//g')
${PYTHON} -m subunit.run discover -s . --list
${PYTHON} -m subunit.run discover -s contrib --list
running=
PYTHON=$(echo ${PYTHON:-python} | sed 's/--source heat//g')
${PYTHON} -m subunit.run discover -s . --load-list /tmp/tmpz6YpAT
${PYTHON} -m subunit.run discover -s contrib --load-list /tmp/tmpz6YpAT
running=
PYTHON=$(echo ${PYTHON:-python} | sed 's/--source heat//g')
${PYTHON} -m subunit.run discover -s . --load-list /tmp/tmpcnciAj
${PYTHON} -m subunit.run discover -s contrib --load-list /tmp/tmpcnciAj
running=
PYTHON=$(echo ${PYTHON:-python} | sed 's/--source heat//g')
${PYTHON} -m subunit.run discover -s . --load-list /tmp/tmplrOgMv
${PYTHON} -m subunit.run discover -s contrib --load-list /tmp/tmplrOgMv
running=
PYTHON=$(echo ${PYTHON:-python} | sed 's/--source heat//g')
${PYTHON} -m subunit.run discover -s . --load-list /tmp/tmppQoXeI
${PYTHON} -m subunit.run discover -s contrib --load-list /tmp/tmppQoXeI
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
heat/openstack/common/db/sqlalchemy/session.py:526: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6
  match = pattern.match(integrity_error.message)
Ran 2316 (+1265) tests in 44.138s (+9.695s)
PASSED (id=4014)
Slowest Tests
Test id Runtime (s)
--------------------------------------------------------------------------------------------------------------------------- -----------
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_autoscaling_group_update_replace_huge_min_in_service 2.264
heat.tests.test_instance_group_update_policy.InstanceGroupTest.test_instance_group_update_replace_huge_min_in_service 1.598
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_autoscaling_group_update_replace 1.588
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_autoscaling_group_update_replace_with_adjusted_capacity 1.474
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_autoscaling_group_update_no_replace 1.312
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_autoscaling_group_update_replace_huge_batch_size 1.222
heat.tests.test_autoscaling_update_policy.AutoScalingGroupTest.test_instance_group_update_no_replace_with_adjusted_capacity 1.144
heat.tests.test_instance_group_update_policy.InstanceGroupTest.test_instance_group_update_replace 1.046
heat.tests.test_instance_group_update_policy.InstanceGroupTest.test_instance_group_update_replace_with_adjusted_capacity 0.936
heat.tests.test_instance_group_update_policy.InstanceGroupTest.test_instance_group_update_replace_huge_batch_size 0.860
___________________________________ summary ____________________________________
  py27: commands succeeded
  congratulations :)

There's a comment in openstack/common/db/sqlalchemy/session.py describing what needs to be done: https://github.com/openstack/oslo-incubator/commit/df3f2bafb