Comment 3 for bug 1211270

Yes, it needs to be in requirements because of keystone.openstack.common.gettextutils:

Traceback (most recent call last):
  File "/opt/stack/venvs/keystone/bin/keystone-manage", line 16, in <module>
    from keystone import cli
  File "/opt/stack/venvs/keystone/local/lib/python2.7/site-packages/keystone/cli.py", line 28, in <module>
    from keystone.common import openssl
  File "/opt/stack/venvs/keystone/local/lib/python2.7/site-packages/keystone/common/openssl.py", line 23, in <module>
    from keystone import config
  File "/opt/stack/venvs/keystone/local/lib/python2.7/site-packages/keystone/config.py", line 21, in <module>
    from keystone import exception
  File "/opt/stack/venvs/keystone/local/lib/python2.7/site-packages/keystone/exception.py", line 19, in <module>
    from keystone.openstack.common.gettextutils import _ # noqa
  File "/opt/stack/venvs/keystone/local/lib/python2.7/site-packages/keystone/openstack/common/gettextutils.py", line 34, in <module>
    from babel import localedata
ImportError: No module named babel