pulp-server -> python-mongoengine -> python-blinker (not found)

[TJM]

When trying to install on a Cent OS 7.x machine, I got the following error:

Error: Execution of '/bin/yum -d 0 -e 0 -y install pulp-server' returned 1: Error: Package: pulp-server-2.16.1-1.el7.noarch (pulp2)
           Requires: python-blinker
Error: Package: python-mongoengine-0.10.5-1.el7.noarch (pulp2)
           Requires: python-blinker
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest
Error: /Stage[main]/Pulp::Install/Package[pulp-server]/ensure: change from 'purged' to 'present' failed: Execution of '/bin/yum -d 0 -e 0 -y install pulp-server' returned 1: Error: Package: pulp-server-2.16.1-1.el7.noarch (pulp2)
           Requires: python-blinker
Error: Package: python-mongoengine-0.10.5-1.el7.noarch (pulp2)
           Requires: python-blinker
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest

I have heard rumors that on RHEL7, you need to enable the extras repo. Should this be handled via "install_options" or something?