Hi,
to install the python-pip, you have to install the epel-release repos: Steps can be found below:
http://sharadchhetri.com/2014/09/07/install-epel-repo-centos-7-rhel-7/
After installing the epel-release repo: (found in the link above)
yum install wget
wget -r --no-parent -A 'epel-release-*.rpm' http://dl.fedoraproject.org/pub/epel/7/x86_64/e/
rpm -Uvh dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-*.rpm
clean up the yum repo.:
yum clean all
and then try installing:
yum install python-pip
Once the installation is complete, proceed to retry the zeppelin installation.
Hope this helps!